Written for a prompt over at 1stclass_kink. Contains (in no particular order): Minor character death, mentions of cold-blooded torture, characters being almost too badass to be real, the glorification of guns and/or knives, OOC-ness, complete and total crack, copious amounts of bad language, attempts at humour by the author, no moral compass, implied torture, implication of someone enjoying carrying out said torture, and mentions of past child abuse. Also, porn, but it's totally relevant to the plot, I swear! If any of this offends, please hit the back button now.

(Cross-posted all over the damn place because I'm a complete comment-whore. I regret nothing :D)

Despite the warnings, it's, uh, really quite cracky? Enjoy :)

. . .

It is a dark and stormy night. A clock strikes midnight somewhere in the distance.

Well, naturally. Whoever heard of a story beginning on a balmy summer's eve, say around eight pm? Exactly.

The only sound to be heard is the soft hiss of falling rain, covering who-knows-what foul deeds that –

"Goddamn, motherfucking shitty weather!"

- yes, well. While in theory, rain is an assassin's best friend, in practice it is actually very much like having God piss on you from an impossible height.

To Erik Lehnsherr, assassin, silently scaling the building that houses his next hit, the rain is about as welcome as a necrophiliac in a morgue. So he is in no mood at all, when he finally lets himself in through a carelessly left open bedroom window, to find his target already bound and gagged and quivering in terror under the gun of a short, slight figure wearing a mask.

A fucking mask. Amateur.

"Oh, what the fuck?" Erik says, irritated.

The figure in the mask turns sharply, a second gun appearing almost out of nowhere to point at Erik, and if he wasn't so pissed, Erik would have to admire the reflexes on the – guy? Looks like a guy, but you can never tell these days and in this line of work it pays not to assume.

"Who are you?" The voice is definitely masculine, and, incongruously, British. Which means there's only one person it could possibly be. And he isn't an amateur, which makes the mask the affectation of a complete and total douche.

"Professor X," Erik sighs, resigned. "Of course."

Professor X relaxes, although he keeps both guns firmly aimed at Erik and the target. His hands don't shake even for a moment. It's quite impressive.

"Magneto," he says pleasantly, like he is genuinely glad to see Erik. "It's nice to finally meet you. I was beginning to think you were just a particularly violent rumour."

"Yeah, great, whatever," Erik says. He points at the target. "This one's mine."

"I've got a .45 that says different," Professor X says, still in that light, conversational tone. He waggles the aforementioned .45 in the target's face without taking his gaze from Erik.

Erik narrows his eyes. "You don't want to get in my way, Professor, I can guarantee it."

"Oh, you're very good, aren't you?" The Professor sounds delighted, which is not the response Erik usually gets to his threats, subtle as they often are. "I see why you have such an amazing body count."

Erik is pretty sure that's the most inappropriate come-on he's ever heard, although that doesn't stop the quick flicker of pride he feels at the words. There's not a lot of love lost in the assassin trade, and it's nice to get some recognition, okay?

"Well then you won't mind if I add one more, will you?" Erik says, and pulls out one of the countless knives he generally has on his person at all times. Preparedness is a mark of the better class of assassin, and Erik is a pro.

"I wish I could let you have it," the Professor says regretfully. "But this chap made some rather unsavoury advances towards a friend of mine, so I'm afraid you'll just have to stand aside and watch as I show him why that was a terribly bad idea."

Erik pinches the bridge of his nose in frustration. He can feel a migraine coming on – he is so not in the mood for this shit. The Professor flicks off the safety on his gun, and Erik has the urge to hurl the knife at him and just get the fuck out of there before he goes postal on the ass of the entire world.

"He passed on information that led to my mother's death," Erik says finally, voice low and angry.

It isn't what he meant to say.

There is silence for a long moment. Even the target, face sweaty and pale with fear, seems to realise that making any sound at all will not go very well for him. Then there is a click as the Professor turns the safety back on his gun, and lowers it.

He steps aside. "Well, have at it, my friend," he says, slightly less cheerfully. Erik wonders if it's because of what he said or because the Professor is just really disappointed he doesn't get to add this mark to his own body count. Well, whatever. Erik has more important things to worry about.

He strides forward and grabs a handful of the target's greasy hair, yanking his head back roughly. The target lets out a muffled scream and starts gibbering away despite the gag in his mouth. Erik grins a not-very-pleasant grin and the target squeezes his eyes shut.

"No," Erik says very softly. He brings the knife up to circle lightly around the target's eyes in a way that is at once gentle and yet unmistakeably a threat. "No, I think you should watch this. Really, I'd hate for you to miss one minute of what I'm about to do to you …"

Twenty loud and rather messy minutes later, Erik finally runs his knife swiftly across the target's throat and lets the twitching, gurgling body collapse to the stained carpet.

He wipes the knife off on the late target's pants and straightens up.

Professor X is still here.

"You're still here," Erik remarks.

The Professor shrugs. "Perhaps I like watching a professional at work," he says easily. "You do wonderful things with a blade, you know."

"Well, that was inspiring," Erik says. "And creepy," he adds, moving back over to the window. "I think I'll be going now."

"Yes, I suppose there's no sense in hanging around," the Professor says, with a half-glance at what's left of the target. "Well. It was good to meet you, Magneto. I hope we'll see each other again."

He holds out a gloved hand. Erik stares at it for a few seconds and then looks up at the Professor's face. His eyes are very blue, Erik thinks, and then wonders why he'd even noticed that at all.

"You are quite strange," Erik tells him conversationally, but takes his hand and shakes it anyway.

"You would not believe how many times I've heard that." Erik can't tell, because of the Professor's ridiculous mask – seriously, what even is that? – but it sounds like he's smiling. "Or perhaps you would."

"I think I would, yeah. Well … Goodbye," Erik says, carefully extricating his hand from the Professor's, since he doesn't seem inclined to let go.

He's out the window and halfway down the fire escape before he hears the Professor's reply:

"I prefer 'see you later'!"

. . .

The second time Erik meets Professor X, he almost gets blown to pieces.

It's just that kind of day.

Erik is following a lead that turns out to not only be false but also extremely hazardous to his health (see: almost getting blown to pieces). He has no idea what the Professor is doing there; he's pretty certain the Professor has no clue either.

He'd asked around about Professor X. In his time as an assassin, Erik has amassed a network of contacts that are varying degrees of crazy and competent, and between them they know almost everyone in the game. What he learns is this:

Professor X is a complete moron.

He always wears that stupid mask. He's unfailingly polite. He's naïve and honourable and nice, he only takes contracts on those he feels deserve it, and he's friends with the Police Commissioner. There are no words for that level of stupid.

And yet.

And yet every one of Erik's contacts agrees that somehow it works. Professor X has been in this business almost as long as Erik has, and that is a long time. How he's managed to remain unknown and completely at liberty while being friends with Commissioner MacTaggert is a total mystery. And the Professor has been known to work with Mystique, ninja extraordinaire in a blue leather cat-suit with the uncanny ability to disguise herself so well that she almost seems to become someone else. That's pretty badass, even by assassin standards.

So, yes, Erik is intrigued. He can admit it.

. . .

"I think," Professor X says between deep breaths. "I think someone may be trying to kill me."

Erik glares at him from where he's bent double, almost hacking up a lung and trying to ignore the acrid taste in his mouth and the unpleasant smell of the alley they're currently occupying. It looks like the kind of alley that even the rats avoid, and Erik is trying very hard to make as little contact with the walls as possible.

"Or you," the Professor goes on thoughtfully. "You strike me as the kind of person people try to kill a lot."

"What gave it away?" Erik says sourly, wiping ash from his brow.

The Professor makes a considering noise. "Well, you're sort of – bad-tempered. And you scowl a lot. I mean –"

Erik rolls his eyes. "For the love of – I meant, what makes you think someone's trying to kill you? Aside from the obvious, of course," he adds nastily.

Eyes widening behind his mask, the Professor says, "I really don't think there was any call for that, Magneto."

He sounds so hurt that, rather than the scathing retort about certain people not living up to their chosen moniker that Erik has lined up, what comes out is, "My apologies. It's … been a long day."

"Apology accepted," Professor X says stiffly, but Erik is too busy trying to figure out what the fuck is going on to hear him. He makes it a point never to apologise to anyone, ever, so why -?

It is at this point that someone starts shooting at them.

"Oh, that is bloody well it," the Professor mutters, pulling out both of his guns. "You know, you try to be nice, you try to bring a little civility to the table, and this is what you get …"

He trails off, still complaining under his breath, and Erik thinks, of all the people to get stuck in a shoot-out with –

Then the Professor brings both guns up and starts firing in the direction of their assailant, ducking behind the wall and darting out when there's a break in enemy fire. His face is set in a sort of pissed off determination and, from the decreasing number of bullets from the other side, his aim is just about perfect. He doesn't flinch when a bullet pings off the wall just above his head; instead he drops to one knee, emptying the left gun's now-empty magazine and slotting in another, all without a break in concentration.

- I'm really glad it was him.

. . .

Erik slowly becomes aware that he's staring but can't bring himself to stop because holy. Shit.

The Professor, meanwhile, is peering around the corner cautiously. "I think I got them all," he says casually, like it's no big deal. He glances back at Erik and adds, a little scathingly, "Thank you so much for your help there, Magneto. I really don't know what I would have done without you. I mean, I might have had to take them down all by myself – oh wait."

Erik could've handled the improbable weapons skills, and he probably could've handled the sarcasm without too much trouble. But this? This obnoxious, snarky badass with pissed off baby-blues and a gun still cooling in each hand?

Erik is pretty sure he's in love.

. . .

"I find it kind of disturbing that his mad skills with a gun get you hot," Angel says, arching an eyebrow. Beside her, Banshee laughs.

"It was two guns," Erik says miserably, feeling his dignity and street cred diminish by the second. Angel rolls her eyes.

"Oh, two guns, why didn't you say so? That makes it much less kinky," she retorts.

From a woman who used to be a stripper, and indeed, has found a use for a stripper pole for which it was never intended (namely, impaling people on it with extreme prejudice), this is a bit galling to say the least.

"She's right, that's sick, dude," Banshee says, still giggling his high-pitched stoner giggle. Erik thinks fondly back to the days when Banshee used to run screaming from the room every time Erik entered it. Good times. "Anyway, I thought you thought he was a moron?"

"That was before he wanted to fuck the Professor's brains out," Angel answers helpfully, before Erik can say anything.

"I hate you both," he tells them instead.

They just smirk at him.

. . .

The third time they meet, Erik saves the Professor's life.

It happens too fast and Erik does it without thinking about it very much and he doesn't remember much about it afterwards, but there's a body with a knife buried in its back and the Professor is blinking up at him with wide, shocked, grateful eyes and Erik is so fucked.

The fourth time they meet, Erik gives up trying to keep track of the number of ways they've both almost been killed.

After an ambush by at least a dozen guys in ski masks – in which Erik keeps getting punched in various parts of his body because he's too busy staring at the entirely distracting sight that is the Professor kicking ass and taking names – it becomes apparent that someone is trying to kill them both.

"This is really starting to piss me off," Erik says.

"It's the fact that they keep sending mindless thugs that annoys me," the Professor agrees. "I don't like killing people without a contract, but I will if I have to."

Erik wishes he wouldn't say things like that. The Professor is really quite unbearably attractive when he lets on that he's actually a capable killer and not the bumbling, good-natured fool most people think he is.

The sudden sound of footsteps shakes Erik out of his reverie. He pushes the Professor behind him and then presses himself against the wall, listening to the footsteps get louder as they get closer. As whoever it is rounds the corner, Erik pulls out yet another knife and makes his move.

There's a brief, confusing struggle, and then things resolve themselves and Erik finds he is face-to-knife with a young woman with red hair and dressed all in blue leather – Mystique. She's got a gun pressed painfully under his ribs and a knee somewhere in the eye-watering vicinity of his crotch.

The stalemate doesn't end until a breathless voice says, "Where were you even hiding that?"

Both Erik and Mystique turn to stare at the Professor, who's open-mouthed and gazing at Erik like he's never seen anything like him in his life. Erik would approve of this if he had any idea what the hell the Professor was talking about.

Mystique, however, seems to know.

"Really?" she says to the Professor, incredulity lacing her voice. "I get attacked out of nowhere by this asshole and all you care about is where he was keeping his knife? What the fuck, Professor?"

To his credit, the Professor tones down the slack-jawed awe, but he rallies almost immediately. "Mystique meet Magneto," he says brightly.

"Oh," Mystique says, looking at Erik with unconcealed distaste. "Magneto. I should have known."

Erik has no clue what the fuck is going on and it's starting to annoy him. He lets go of Mystique with a scowl and pockets his knife again.

"Anyone gonna explain things to me, or do I have to guess?" he snaps. "I don't like guessing games, just for the record."

"My God, you're a douche," Mystique marvels disgustedly. She looks back at the Professor. "This guy, really?"

The Professor claps a hand to his masked face in embarrassment. "Mystique, please."

"What? I'm just saying, I don't get it at all –"

Speaking loudly enough that he drowns her out, the Professor says to Erik, "Mystique is a friend of mine. We've worked together occasionally. She's usually much nicer than this," he adds earnestly.

"No I'm not," Mystique says under her breath, and even though Erik has just met her, he has a feeling she's being more truthful than the Professor.

"Anyway," she goes on. "I got your message. I'm guessing they –" she points at the bodies scattered on the ground around them "- are the reason you called?"

The Professor nods regretfully. "Yes. Whoever has it in for Magneto –"

"Both of us," Erik interrupts indignantly.

The Professor waves a hand distractedly as if to say details, details, and goes on with, "They get points for determination, but they're clearly not very bright."

"I don't know, Professor," Mystique frowns. "I think maybe you should lay low at the mansion for a while. Just until this blows over."

The concern in her voice makes Erik feel slightly more warmly towards her. Anyone who so obviously cares for the Professor is someone that he can at least be civil towards.

"I can take care of myself, you know," the Professor says, slightly exasperated.

Mystique raises an eyebrow. "Oh, Professor," she says wryly. "You really can't. If it wasn't for Magneto here, you'd be –"

"Well, see, he was here, so I don't see what –" Professor X starts to protest but Mystique interrupts him.

"He might not always be there," she says bluntly.

Okay, no, she's a total bitch, Erik takes back every nice thing he just thought about her

"I'm standing right here," Erik points out, because he genuinely thinks they've both forgotten.

Mystique narrows her eyes at him, but Erik has been eyeballed by the White Queen, for fuck's sake, he can totally take it.

Eyes watering slightly, Mystique looks away. Erik grins at her triumphantly. She gives him the finger and then drags the Professor off to the side to hiss furiously in his ear. Professor X glances back at Erik sheepishly and Erik can feel the grin sliding right off his face as he looks into those ridiculously blue eyes.

A few minutes later, Mystique strides back over to Erik.

"I don't trust you as far as I can throw you," she says, as subtle as a 12-gauge, "but the Professor insists –"

"I really do," Professor X butts in helpfully. Mystique elbows him sharply in the ribs.

"And since it's his place, you're welcome to hide out there with him until the heat on you dies down," she continues. "But I've got my eye on you, Magneto, so don't try any bullshit, you got it?" She pokes a finger in Erik's chest once or twice for emphasis.

Erik looks down at her hand and then slowly lifts his gaze to her face.

"You know," he says casually, "I've killed people for less than that."

The Professor makes some sort of high-pitched noise behind Mystique, who rolls her eyes so hard it looks like she's in danger of spraining something and mutters, "Colossal douchebag, seriously, what the fuck is wrong with you," as she stomps away.

. . .

It turns out Mystique brought a car with her when she answered the Professor's emergency message. Erik sits in the back while she drives, and is surprised when Professor X shares the backseat with him.

The Professor talks at him all the way to wherever it is they're going, but all Erik is really aware of is that fact that their hands are touching on the seat between them. It's all very innocent and eighteenth Century, except the Professor's voice stutters every time one of them moves their hand or they go over a bump and Erik is trying very hard to talk himself out of an erection.

It's almost a relief when the car finally rolls up to a huge, sprawling estate somewhere in the New York boroughs, although then Erik is left staring like an idiot as a butler – a fucking butler, for Christ's sake – holds the door open and Mystique leads the way inside.

"I," he begins, and then they walk past a library stacked floor to ceiling with books and he has to start again. "Maybe this wasn't such a great –"

"I'll show you to your room, shall I?" the Professor interrupts nonchalantly, and it occurs to Erik that the Professor might have been expecting his reaction. He puts a hand under Erik's elbow and steers him up the frankly ridiculous staircase, and, slightly dazed, Erik lets him.

He hears Mystique snort with derision behind him but decides he doesn't really care why, especially when he and the Professor pull up in front of a room that, once Erik opens the door, turns out to be kind of the most perfect room ever.

The Professor laughs at Erik's blatant astonishment and says, "I hope you'll like it here."

"It would be impossible not to," Erik says honestly. He turns to the Professor and adds, haltingly, "Um. Thank you. For this. It's – really nice of you …"

"Oh, it's quite alright," the Professor says, waving a hand vaguely and sparing Erik further agony. "We don't get many … guests, and this house is so big, it's nice to have people here."

There's a short silence and then the Professor taps the doorframe lightly and says, "Well, yes, anyway, I should let you get some sleep. My room is just across the hall …" He trails off as Erik stares first at him and then at the door opposite this one.

"Oh," Erik manages. He bites his lip nervously.

"If – if you need anything," the Professor says distantly, his gaze fixed on Erik's mouth, "just. Knock."

"Right," Erik mumbles. There's barely a foot of space separating them.

They stare at each other for a few more minutes, and Erik feels like something is expected of him, but then the Professor says, "Right," and moves away to cross the hall.

He's at the door to his room when Erik unsticks his throat and calls out, "Goodnight." The Professor stops with his hand on the doorknob and glances over his shoulder.

His smile is blinding when he says, "Goodnight."

. . .

It becomes apparent, somewhere between a truly spectacular breakfast and an equally magnificent tour of the mansion, that the Professor is … well.

He's kind of a nerd. A sexy nerd, don't get him wrong, but still. A nerd.

There are books everywhere – not just in the library, the countless studies, bedrooms, and sitting rooms, but in the kitchen, and the wine cellar, in every one of the bathrooms, and there are at least a dozen closets overflowing with them. And they all have long, complicated titles like Advances in Genetics: Tissue-Specific Vascular Endothelial Signals and Vector Targeting, Part A, and Pcr Applications: Protocols for Functional Genomics, and even, Transcriptional Regulation in Eukaryotes: Concepts, Strategies, and Techniques. Whatever the hell any of that even means; Erik gets a headache just looking at them.

And this would be fine if the Professor, having seen Erik staring at the books with his head tilted to one side, trying to understand if they're even in English (they are. Just about.), didn't mistake Erik's simple confusion for interest. Because then Erik gets a three hour lecture about "the beauty of the human genome, Erik, it's indescribable, truly," and "you and I share a mutation, you know – did I tell you my specialty was mutations, well it is, and we both have a mutated MC1R gene, otherwise known as blue eyes -" and then, "do you have much interest in genetics, Magneto?"

At which point Erik, shaken out of a bored stupor by the question, says, "Not really," without thinking, and then, as the Professor's face crumples, adds hastily, "I mean, I've never really thought about it that much."

The Professor still looks slightly put out, so Erik, who's always been a soft touch for kicked-puppy expressions, quickly casts about for a distraction.

He finds it in a chessboard sitting innocently on a nearby table. When the Professor follows his gaze he says, in the strained tones of one trying to keep the excitement out of his voice, "Do you play?"

"I haven't in a while," Erik says, after a pause that he hopes went unnoticed.

"Capital," Professor X says, clapping his hands together. "I'll go see about getting us something to drink while you set up the board, yes?"

Erik nods and the Professor smiles and exits the room, muttering to himself about tea.

"He'll keep you playing for hours, you know," says a quiet, knowing voice behind him.

Erik absolutely does not jump at the sound. You can't prove it, and anyway, he'll just deny it. Instead he turns to find Mystique curled up in an armchair, reading a book. She hasn't even bothered to look up.

"Do you often lurk in dark corners just waiting to ambush unsuspecting people?" Erik asks, irritated and annoyed at the fact that he's irritated.

"I'm hardly lurking in a dark corner," she replies, sounding amused and gesturing to the dozen or so lamps that are currently lighting the room. She looks up at him and adds, "And I doubt you've ever been unsuspecting in your life."

She has a point.

Disregarding this completely, Erik says loftily, "What were you saying about the Professor?"

"Just that he'll be glad to finally find someone to play that stupid game with." Mystique turns a page idly. "I stopped after he kept trying to lose on purpose to make me feel better. He'll keep you playing well into the morning if you let him." She flicks a glance up at him and says, slyly, "I get the feeling you wouldn't mind that at all."

Erik is not blushing, it's just that it's … warm in here. Yeah.

"You know, even though you're the kind of trouble we can do without, you're good for him." Mystique closes her book, turning serious. "Like just there, when he was doing his whole –" she waves a hand vaguely "- genetics spiel. Most people would've walked out, I think. You just stood there and … listened."

Erik feels slightly guilty at this, because he hadn't exactly been listening, not that he's going to tell Mystique that.

"He does that a lot then?" he asks, trying to get the conversation onto safer ground.

Mystique nods. "Oh yeah. He's a genetics professor at NYU, and you will never meet anyone more suited to the job."

"So the nickname … isn't actually a nickname?"

"Nope. It's a job description." Mystique looks briefly alarmed. "I probably shouldn't be telling you this," she says uncomfortably. "He wouldn't want it to get out that he's a for-hire killer by night. It could ruin his career." She descends into thought for a few seconds. Then she shrugs. "Ah, what the hell. He's earning more as an assassin anyway."

Erik doesn't really know what to say to this, besides a heartfelt promise that he won't breathe a word of it to anybody, but that would just be embarrassing for all concerned so he keeps a lid on it. Thankfully, he is spared the trouble of coming up with something else when the Professor re-enters the room carrying two crystal tumblers and a bottle of scotch.

"I thought you were getting tea?" Mystique says, arching an eyebrow at him.

The Professor shrugs. He avoids her eyes as he says, "I thought Magneto might prefer something stronger."

Mystique smirks. "Uh-huh. Sure you did."

"Anyway," the Professor says hurriedly, "have you got that board set up, Magneto?"

"Just about," Erik says, putting the last few pieces in their respective places. "I should warn you," he says, as he sits down, and the Professor takes the seat on the other side of the table, "I'm very good."

The Professor takes a long, slow sip of scotch, and then shoots him a smile that is just shy of filthy and says, "I'm better."

When Erik loses the game a disastrous forty-five minutes later he blames it entirely on Mystique, but he knows he's not fooling anyone.

. . .

Not being able to take a contract is making Erik kind of twitchy.

It doesn't help that Mystique can and does go out regularly to relieve people of their existence, and, occasionally, various body parts. Every time she does it she grins at Erik on her way out the door, and he has to fight down the urge to plant a boot in her throat, he's that jealous.

What also doesn't help, although in quite different ways, is the fact that being unable to do his job means he's often in close proximity to the Professor. This makes Erik twitchy for a very different reason.

Namely that if he has to sit through one more chess game with the Professor smirking suggestively at him – and twiddling the pieces between those long, pale fingers, and biting his indecently red lips while considering his next move, and staring at the board so intensely that Erik can't help but wonder what that intensity would feel like in other, much more enjoyable scenarios – well, Erik's going to drag the Professor across the table and either fuck him or kill him.

It says something about Erik's state of mind that he can't quite decide which of those would be more satisfying.

. . .

Since the Professor also has a day job, Erik only really sees him at night, although this is quite enough, in that way that it's not actually enough at all.

And because the Professor is so damn cheerful all the time, Erik assumes the lack of a bit of healthy contract killing isn't bothering him nearly so much as it is Erik.

So it comes as something of a surprise, early one Wednesday morning, to hear the sounds of destruction coming from one of the studies and, upon going to investigate, discovering that the Professor is the one behind it.

He's currently in the process of ripping the pages out of some book, and Erik winces because he hates to see any book being treated that way. (Even those trashy vampire novels that the Professor swears he doesn't read but has nevertheless got first editions of in his collection).

"Everything alright?" Erik asks lightly, as the Professor tosses the ruined book aside and picks up the nearest lamp.

"Oh, yes, everything's just peachy," the Professor says, hurling the lamp across the room with surprising venom. "Why on earth would you think otherwise?"

Erik wants to say, because you've thrown half of your beloved thesis into the fire, but the crash of the lamp sailing straight through the window stops him. Also, the Professor might cry. He loves that fucking thesis.

"You seem … tense," he hazards, and then realises how ridiculous that sounds. He's just not sure what to say; he's never seen the Professor like this.

"Do I? Well, that is strange, I wonder why I'd be tense." The sarcasm is still attractive, Erik would just like to point out, even if it does sound bitter and helpless in a way that he's never associated with Professor X. "Can you think of any reason why I'd be tense, Magneto?"

Erik thinks he has a good idea about the reason behind the Professor's tension because it's same one he's been suffering for the past few days – the inability to go out and kill some deserving motherfuckers, and an epic case of blue balls, although that last one might just be him. Before he can commiserate, however, the Professor whirls around to face him.

His hair is crazy and makes him look like he's just received an electric shock, and his eyes are wild when he says, "I'm going fucking stir crazy in this house. I go from here to work and back again and I haven't so much as –" He breaks off with a frustrated growl and kicks at a small side table viciously, sending it and everything on it careening across the room. "I haven't taken a contract in days and it's driving me insane, and I know it shouldn't, I should be able to, to rise above it or some rubbish, but if I could just take one, just one …"

He trails off and leans on the back of the sofa. Erik watches the taut lines of his shoulders with a mixture of lust and sympathy, because he gets it, he totally understands where the Professor is coming from.

Fun fact about assassins: they like to say they're only in it for the money, like if they could find something that pays better they'd give it up in a heartbeat, but it's a lie. There's nothing like watching a target beg and plead for mercy, seeing the life and blood leave their pathetic, fragile bodies and knowing you'll get to do it all over again the next night, and the next, and the next … The truth of it, the real truth, is that killing is addictive, and every assassin is only two steps and a twisted sense of morality away from being a serial killer.

Getting paid to do it is just a way to keep score.

"Have you tried the gun range?" Erik asks quietly. It's not enough, not nearly enough, but maybe shooting off a few rounds will help the Professor in some small way.

The Professor lets out an awful, near-hysterical laugh. "If I pick up a gun I'm going to kill someone, and it might just be you."

There is no reason why that should make them both go utterly still, or why Erik's stomach goes molten with want and he can hear his heart pounding in his ears. And there's certainly no reason why it should make him want to pull the Professor to the debris-strewn floor and fuck the frustration out of them both. The fact that it does is just another mark of how screwed up they both are. As if Erik needed the reminder.

"You just," Erik chokes out, "you just need a distraction."

"So distract me," the Professor says desperately, his hands biting into the back of the sofa, and that is it.

Erik is across the room and pushing the Professor up against a conveniently located desk before either of them knows what's happening.

"This," the Professor says, swallowing hard. "This wasn't what I had in mind."

"Liar," Erik hisses into his ear, and digs his fingers into the Professor's thigh.

"Alright, alright," the Professor gasps out, spreading his legs in a way that makes Erik curse loudly. "This was exactly what I had in mind, and if you don't touch me in the next five seconds I will fucking end you."

"Jesus Christ," Erik mutters, and then, "Threats are not sexy."

The Professor laughs and wraps his legs around Erik's waist. "Now who's the liar?" he breathes, and starts pulling Erik's shirt out from his pants.

Erik can't even remember what they were talking about. He just stares at the Professor's mouth and thinks how much he wants to kiss him and wondering how much that fucking mask is going to get in the way of him doing just that.

"Take it off," he says, leaning into press a kiss to the Professor's neck. "The mask. Take it off."

The Professor goes still, though not for long as Erik hits a spot on his neck that makes him squirm and clutch at Erik with a whimper.

"But I –" he says finally. "I can't – I –"

"No offence, but it's a stupid fucking mask," Erik tells him, and then bites at his collarbone. "And more than that, I – I want to see you." He slides his hand down to the Professor's ass and pulls him forward so that he's pressing down on Erik's dick, and they both let out a startled groan. "Please."

"Oh, god." The Professor sucks in a breath, his nails digging into Erik's back under his shirt, and then, in a rush, says, "Yes, whatever you want, take it off, fucking burn it if you want, I don't really give a –"

"Hey, Professor, what the hell, man, I've been ringing the doorbell for like – oh, my god, my eyes!"

Erik has a second to register another voice, and then he's on his back on the floor, and a guy in blue leather and glasses – seriously, what is it with these guys and blue leather? – has his hand around Erik's throat. Distantly, Erik can hear the same voice in the background wailing, "My eyes, I think I'm scarred for life, Jesus Christ, my eyes!"

Then the Professor pushes the guy in glasses aside and helps Erik up, and while Erik massages his neck and takes deep breaths, the Professor says, sternly, "Boys, I'd like you to meet Magneto."

"Oh, shit," someone says.

. . .

"Listen, man, we're really sorry we interrupted you and the Professor, uh, y'know," says the tall, black guy that Erik now knows is Darwin.

"Yeah," grimaces the blond kid, otherwise known as Havok. "Like, unbelievably sorry, you have no idea. I'm never gonna be able to get that image out of my head." He shudders theatrically.

"Also, I apologise for almost killing you," says the one in the glasses, who Erik had been surprised to find out was Beast. He'd heard about Beast before and about how exactly he got that nickname, and Erik had emphatically not been expecting the guy to look like he does, which is basically like an anxious, nerdy hipster kid.

Erik doesn't really feel like speaking right now, so he just stares the three of them down and takes a seat on the sofa. The Professor is still over by the desk and there's a bright red mark on his collarbone and it's really not helping matters at all.

Erik wouldn't have minded being interrupted, but he hadn't even gotten the Professor's pants open. That's what's unfair about this whole thing.

"I can't believe you tried to kill him," the Professor admonishes Beast. "What on earth were you thinking, how could you even think –" He breaks off, apparently to angry to finish the sentence.

"He looked like he wanted to eat you!" Havok protests, in Beast's defence.

What am I, a fucking shark? Erik thinks to himself, but wisely decides not to intervene.

"Well maybe I wanted him to!" the Professor explodes.

"Oh, ew, Professor!" Havok yells, throwing his hands up to cover his ears.

"Yeah, man, too much info," Darwin agrees, and the Professor looks chagrined.

"Alright, that was tasteless, I'm sorry," he says, sounding very much like he's regretting ever saying anything, ever.

"That's what she said," Beast mutters, but not quietly enough.

There's a short silence, and then Havok cracks up. "Dude, high five, that was classic!" he grins at Beast, and holds up a hand. Smiling slightly, Beast high fives him, while in the background Darwin rolls his eyes and the Professor facepalms so hard his mask makes an ominous creaking noise.

"You've been hanging around Havok too long," he tells Beast, who just shrugs unrepentantly, still grinning.

"And this is the future of the assassin trade," Erik remarks to the Professor, who's fighting a smile.

"I know, I weep for humanity – more than I usually do, at any rate." He pushes himself off the desk and stands in front of the three boys. "Now, since you've apologised and there's no permanent harm done," he casts a pointed glance back at Erik's throat, and even though Erik knows it was meant mostly for Darwin, Havok and Beast's benefit, he can't help blushing and thinking about the Professor's mouth there, kissing away the bruises left by Beast's hand and leaving others in their wake.

He zones out for a while on this beautiful image and when he tunes back in the Professor is saying, "- I'm sure we all have a lot of things to do today, so perhaps you should go and do them?"

"But Professor," Havok interrupts plaintively. "You promised Bozo here you'd teach him how to shoot properly, and Mystique said she'd spar with me and Darwin the next time we came over."

"Well remembered, Havok," the Professor says sourly, after a pause in which Erik can practically see him looking for a way out of his promise and finding nothing. "Alright, fine, but only for a couple of hours, and if any bones get broken, I take absolutely no responsibility for them, understand?"

"Yes, Professor," the boys chorus, and then dash out of the room excitedly.

"Sorry about this," the Professor says into the silence. "I honestly forgot I'd promised to help them."

"It's fine," Erik says, waving the apology away, because the Professor has absolutely no reason to apologise. "I'll be here when you've finished. Oh, and Professor?"

"Hmm?" the Professor says distractedly, mind already on teaching Beast the wonders of the gun range.

Erik grabs at his arm as he walks past and drags him down. He presses an awkward but heated kiss to the Professor's mouth around the mask, and then whispers, "Try to get rid of them soon, won't you? I have plans."

Dazed but beaming, the Professor wanders out of the room. Behind him, Erik smirks and anticipates the rest of the day.

. . .

At around midnight, Erik gives up waiting and goes to knock on the Professor's door.

There's no answer. Not even when he knocks a second, third and fourth time.

There's maybe two reasons why there's no answer. Firstly, that the Professor is ignoring him, which Erik supposes is possible but thinks is unlikely because he's not actually a fourteen-year-old girl and crippled with self-doubt. He's fairly certain the Professor wouldn't ignore him; even if he didn't want to speak to Erik, he'd still do it, out of some warped sense of nobility.

So that leaves the second reason: the Professor's not in his room. Which is more troubling, because Erik's searched the rest of the mansion and he's not anywhere there either.

He wouldn't have gone on a job, Erik thinks, and then stops in the middle of the hallway.

Of course he would've gone on a job, you moron! he thinks to himself. You saw him this afternoon, he would've wrecked the entire house if you hadn't distracted him with filthy almost-sex!

Erik paces the hall, trying to think of all the people the Professor could possibly have gone after. He comes up blank and swears out loud for a few minutes. It makes him feel better, but not by much.

Unlike Mystique, Erik knows the Professor can take care of himself when he's out on a job. But, also unlike Mystique, he knows exactly what state of mind the Professor's in, and how it's likely to make him more reckless and less focused on keeping any eye out for trouble. The only reason Erik and the Professor had survived all those attempts on their lives is because they'd been watching each other's backs, however unconsciously.

The thought of the Professor without back-up makes Erik feel sick.

And angry. Very, very angry.

Mind made up, he strides away, pulling his phone from his pocket and making a few calls.

(But, because there's secretly a fourteen-year-old girl in all of us, not before knocking on the Professor's door a fifth time. Just to make sure).

. . .

Another fun fact about assassins: they're completely fucking insane.

. . .

"You know," the White Queen says pleasantly, sitting back in her chair and crossing one white-booted leg over the other, "this would have gone much better for you if you hadn't burst in and tried to threaten me."

Erik is starting to realise this, thank you very fucking much. He strains against the hold that the White Queen's lackeys, Azazel and Riptide, have on him, but he might as well have tried to kill them with his mind for the all the good it does him.

"Now," the White Queen goes on. "I'm going to tell my boys to let you go, but you so much as reach for one of those ridiculous knives that are obviously compensating for something, and you'll be dead before you hit the ground. Understand?" she adds sweetly, but with a poisonous edge that tells Erik she's being deadly serious.

He nods once, and then Azazel and Riptide cautiously release him. His hands are itching for a weapon but he just clenches his fists and looks directly at the White Queen.

"You know about every contract going," he says tightly. "I need to know which one Professor X took."

"Professor X?" the White Queen echoes, raising an eyebrow. "Why should you care about which contracts the Professor takes?"

At that moment, Azazel leans down and whispers something in her ear. Erik watches her face change from puzzlement to disbelief to a wicked smirk that, despite Erik's hardened resolve, sends a thrill of apprehension down his spine.

"Magneto," she says delightedly. It's so different from the way the Professor says it that Erik wishes even more that he had a knife in his hand. "You and the Professor? I had no idea. Have you managed to get that stupid mask off him yet?"

"It's a work in progress," Erik says shortly, even though he knows she only said it to fuck with him.

"Well, that's a shame, I'm sure we'd all love to know what he looks like under there." The White Queen stares up at him with that evil fucking grin on her face. Erik wants to cut it off her so badly.

"I'm sure you would," he says, his voice a low curl of anger. "But you're not going to, you manipulative bitch, because he's mi –"

He stops himself from finishing that sentence but it's too late. The White Queen's eyes flash triumphantly and Erik wants to hit himself now. He always did have issues with sharing.

"Yours, is he?" the White Queen says, and her voice takes on a mocking tone. "But you don't even know where he is."

That's it. Erik is so done with this bullshit.

He grabs Riptide and flings him across the room to collide with Azazel, and then before either of them can recover, he dives over the desk between him and the White Queen and wraps his hand around her throat.

She doesn't struggle, which is maddening. He tightens his grip a fraction; he can feel the cartilage in her windpipe creak under the pressure. Her face goes red and then purple but she still does nothing except gesture at Azazel and Riptide to stand down, all without taking her eyes from Erik.

"Kill me," she manages to choke out. "Go – on! But you'll never – find him – without me!"

For a moment, Erik thinks that killing her would be a good trade-off, but then it hits him that she's absolutely right, that no one else would even know where to start looking for the Professor, and he lets go of her neck and pushes her away from him in disgust.

She gasps in a breath and rubs at her throat. "Marko," she spits at him hoarsely. "Cain Marko. That's his next target. Now leave."

"But," Erik says, half to himself. "What – Marko's second-rate, why would anyone waste their time –"

"This isn't fucking twenty questions, Magneto!" the White Queen snarls, and now she has a white-handled revolver clutched in her hand and aimed right at him. Azazel and Riptide are circling Erik, waiting for her signal. "I gave you what you wanted, so kindly –" she squeezes the trigger, pulling the gun up at the last second so that the bullet goes slamming into the ceiling instead of Erik's forehead "- get the hell out!"

Erik goes.

. . .

"The White Queen," Angel echoes. "The White Queen."

"That's what I said."

"Magneto?"

"Yeah?"

"Are. You. Insane?"

A bitter laugh.

"Well, obviously. So what else is new?"

. . .

Erik follows Angel's careful instructions but ignores her, "you owe me big time, daddy-o," and is soon creeping across Cain Marko's front lawn.

There's only one light on, shining through a downstairs window and illuminating the night. Erik finds this incredibly ominous but doesn't stop moving forward. He unpicks the lock on the front door in a matter of seconds and then he's running silently through the house until he comes to the right room.

Marko is laid out on the floor, wrists and ankles tied together, gag over his mouth. His face is bloody and bruised and he's moaning piteously through the gag. One of his eyes has swollen shut, and there's a wound in the side of his head that looks just like the butt of a gun.

The Professor is standing over him, breathing heavily. He's not wearing gloves and his hands are bright with blood and curled around his gun like it's a lifeline. He's shaking and wild-eyed, and there is hatred and fury in every line of his body as he looks down at Marko.

He's the most beautiful thing Erik has ever seen.

You know. Except for that mask, because wow, that is one ugly piece of shit.

"So I'm guessing now's not a good time?"

Erik keeps his voice light and casual, not because he's worried the Professor might shoot Marko – it's what he's here to do, he accepted the contract, Erik's not going to get in the way of that – but because the Professor might shoot him.

"You could say that," the Professor says, his voice brittle. "What are you doing here, Magneto?"

"I seem to recall we had a date, Professor," Erik says pointedly. "Of course, this isn't exactly what I had in mind, but," he gestures around at the room, "I'm sure we could work something out."

The Professor doesn't say anything, he just keeps staring down at Marko like he's having a hard time deciding what to do next.

"Of course, I can see you're busy," Erik goes on conversationally, taking a seat and making sure to keep both of them in his sight-line.

"Yes," the Professor says shortly. "I have some … trash to take out."

That was, Erik thinks wryly, the worst fucking one-liner in the history of ever.

"Sorry," the Professor says after a pause. "That was terrible."

"Yep," Erik agrees.

"I can do better, you know."

"I'm sure you can."

"But not right now."

"No."

The longer the silence goes on, the less intimidated Marko seems to be. He rolls himself into a vaguely upright position and glares at the Professor with his good eye. Erik has the fleeting desire to rip it out but quashes it reluctantly. This is the Professor's show, all Erik can do is make sure he gets a good seat.

"Why him?" he asks eventually, because he's genuinely curious. "He's – nothing. He's barely even worth the bullet."

Marko lets out a muffled shout in which the words 'fuck you' are very much perceptible, and a word that Erik doesn't recognise, but which, judging by the way the Professor tenses up, might just be the Professor's name.

His real name.

Erik's not going to lie; he's jealous as fuck that this asshole knows the Professor's actual name while he doesn't, but he's still curious.

"He's my stepbrother," the Professor bursts out suddenly, and if it could, Erik's entire head would have exploded just then.

"Your – ?"

"Stepbrother, yes," the Professor says impatiently. "His father married my mother when I was ten."

"And …?" Erik says, because that just can't be the whole story. There's a black little suspicion building up in the back of his mind about what the rest of the story might be though.

"And nothing!" the Professor snaps, and the panic and fury in his eyes confirms exactly what Erik is thinking.

"Professor," he says quietly. "What did he do to you?"

The Professor lets out one of those terrible, mad laughs. "What did he do to me?" he repeats shrilly. "That is not a nice story, Magneto, not nice at all. You sure you want to know?"

"Yes. Tell me."

The Professor tells him.

. . .

There is a long and deafening silence when the Professor stops talking. He sags slightly, as though exhausted, and Erik wonders how long he's been keeping this dark and disgusting secret to himself. How long he's been made to keep it.

The anger boils up in Erik's stomach – anger at the world for letting something like this happen, anger at himself for asking the Professor to relive it, anger at the Professor's mother, a woman he has never met and who's long dead by now anyway; hell, even anger at the Professor for never saying a word to anyone. But most of all, he's furious at Marko for doing it, for getting away with it, and for sitting there without any kind of remorse for what he's done.

Erik wants to tear him to pieces. He wants to rip shreds off him, inch by inch, break every bone in his body, set his nerves alight with excruciating pain – then put him back together so he can do it all again. And again. And again …

But.

But it's the Professor's show. And Erik won't deny him the satisfaction of doing all that himself.

"I see," Erik says slowly.

"Do you?" the Professor hurls back. He aims his gun at the nearest wall, lets off a volley of shots, and then swings around again and presses the now white-hot muzzle to Marko's forehead.

The screams that follow make both the Professor and Erik shudder, only partly in distaste.

Erik makes a decision and stands up. He pulls out a knife – his favourite, if he's going to be honest – and hands it, handle forward, to the Professor.

"Take it," he says, so quietly it's barely more than a breath. "Do anything – do everything to him. Everything you've ever thought of."

"I," the Professor whispers. "I can't, I –"

"Yes you can. You want to."

"Yes," the Professor half moans. "God, yes."

"Then do it," Erik says, pressing the knife handle into his hand and holding onto both just a little too long. "I won't stop you. I won't interrupt. He's all yours."

"Fuck," the Professor says, and then he's kissing Erik so hard he can't breathe or think but that just makes it better somehow. The Professor's mask is digging painfully into the bridge of his nose, but even that feels good right now, and the tang of copper as the Professor bites at his mouth is just beautiful.

"Have a seat," the Professor says, as he pulls away, panting. He flashes Erik a grin that Erik thinks is gorgeous but is probably really fucking scary and adds, "I want you to watch."

His eyes are glinting with a bright, crazy malice as he drags Marko up by the hair, and Erik finds his seat without taking his eyes off them, his mouth dry, his heart in his throat, and painfully hard because -

Because if the Professor is beautiful with a gun, he's fucking magnificent with a knife.

. . .

It starts in the car, on the driveway of the mansion.

Well. Not exactly. Really, it started nearly three weeks ago when the Professor had flirted with him shamelessly over a cooling corpse. But for all intents and purposes, it starts here, now, when the Professor kills the engine and then looks down to where he's clutching Erik's hand hard enough to bruise and Erik's holding back just as tightly.

(They'd held hands all the way back to the mansion, in a way that said quite clearly they were in desperate need of something to hang on to, for everyone's benefit).

"Do you … want to talk about it?" Erik says hesitantly, because he knows a hundred and one ways to make someone talk but this is the only time he's ever hoped he doesn't get an answer.

"No," the Professor murmurs. "Hell no. I don't even want to think about it again, so talking about it? No, absolutely not."

"Okay," Erik says, and the Professor lets out a breath.

"One thing I would like to know, though," he says. "How did you even find me? I know I didn't leave a trail behind, so how -?"

"The White Queen," Erik admits, and watches with raised eyebrows as the Professor smacks himself in the forehead in realisation.

"Of course," he sighs, shaking his head. "Everything gets back to her, of course she'd know. But she's not exactly known for her hospitality, how did you even convince her to tell you about … the contract?"

The careful omission of Marko's name is just one of many things about the man that makes Erik wish they hadn't ripped him apart already, because he'd really like to go to town on the bastard for leaving such a visible mark on the Professor.

So his grin is a little too sharp and his voice a little too harsh when he says, "She just needed a little persuasion."

"Oh, god. What did you do to her?" the Professor asks in a hushed voice. His nails dig into the back of Erik's hand and Erik's breath hitches at the flare of pain as he tells the Professor everything that happened with the White Queen.

"– I could feel her pulse, I could feel her spine, Professor, it was – it was –" he finishes in an exultant whisper, and the Professor shudders in the seat beside him and turns hot, blue eyes on him and says, "Get out."

Confused, Erik says, "What –" but the Professor interrupts him.

"The car," he snaps. "Get out of the car, Magneto."

"But why –"

The Professor pushes at his shoulder frantically. "Because," he hisses, "in about thirty seconds we're going to fuck each other stupid, but we're not going to make it to a bed, and there just isn't enough room in this car for what I had in mind. So get out. Of the damn. Car."

Erik gets out of the car so fast he almost breaks the sound barrier.

. . .

The Professor's right.

They don't make it to a bed.

They barely even make it through the front door.

. . .

They stumble their way to the stairs, Erik's hand fisted in the Professor's hair and the Professor trying and failing to get them both out of their clothes. There's a moment where they almost topple backwards but the Professor manages to steady them and then drags Erik down to the ground anyway.

Erik curls one hand around the Professor's neck while the other goes to work on the buttons of the Professor's shirt, and he presses open-mouthed kisses to the Professor's throat in between buttons until the Professor distracts him with his mouth and then he just tears the shirt open.

Buttons ping off in all different directions as he goes to kiss the Professor again, but he's impeded by the mask and he clutches at the Professor's shoulders and growls, "I'm going to rip that fucking thing off you if you don't –" and then he breaks off as the Professor reaches up and does it for him.

"I thought you'd never bloody ask," the Professor gasps, throwing the mask aside, and then Erik finally gets a look at him.

He's – pretty, is the first word that comes to Erik's mind, and he is, all flushed cheeks and bright eyes and kiss-bruised lips, but close on the heels of that thought is the word perfection and Erik makes a low, punched-out sound and kisses every inch of him he can reach.

"Magneto," the Professor says, and Erik breathes, "It's Erik, call me –" and he's on the verge of saying, actually, you can call me whatever the hell you want, when the Professor laughs delightedly and says, "Erik," in what is possibly the sexiest way anyone's ever said his name and Erik's whole body lights up.

"Shit," he says, with feeling. "Say it – say it again."

"Erik," the Professor repeats, and then, "Will you get your damn pants off, god, do I have to do everything –"

"Tell me your name and I'll fuck you through the floor," Erik promises, grabbing the Professor's hand before it can reach his belt.

There's a hot, tight silence, and then the Professor bursts out with, "It's Charles, Charles Xavier, and don't you dare laugh or so help me I will –"

"Charles," Erik says, testing it out. He kind of doesn't want to say anything else now.

"- oh," the Prof – Charles says, cutting off his own rant. "That's." He swallows. "That's actually really fucking sexy, god, say it again."

Erik does, and then Charles is kicking off his shoes and tearing at the front of his pants and struggling out of them and the boxers underneath, and Erik shoves his way between his legs and wraps his hand around Charles' cock. Charles goes absolutely still under him for a second and then grabs Erik by the hair and kisses him messily, panting out, "God, Erik, you, yes," and throws his head back, not even seeming to notice when it thuds against the stairs.

He makes an absolutely filthy picture, writhing against the stairs with his shirt hanging open and his legs spread wide, and as much as Erik is enjoying the view, he just really, really wants to fuck Charles until neither of them can walk, so he takes his hand away, and presses two fingers against Charles' mouth when he groans his disappointment.

"No lube," he explains, when Charles falls silent and stares at him. "Have to do this the old fashioned way."

"What –" Charles begins, chest heaving, but Erik pushes in gently and he stops talking and sucks on Erik's fingers instead.

"Oh, fuck, fuck," Erik says, as Charles' tongue does impossibly dirty things to his fingertips, and Erik imagines what it would feel like on his cock and has to take his hand away before he comes in his pants.

Charles is grinning smugly as Erik kisses his way down his chest, but it disappears when Erik licks at a nipple and then bites it, and becomes a hoarse whimper when Erik just keeps moving south and folds Charles' right leg to his body, all while avoiding his cock.

"What are you –" Charles starts, lifting himself up on his elbows, but then Erik bends his head and does something that makes him squeak and then let out a long moan. "Oh. Oh. You – you're –" He can't seem to get his words out.

"Told you," Erik says, lifting his head and murmuring the words into the back of Charles' thigh. "Old fashioned way."

And then before Charles can say anything else Erik lowers his mouth again and slides his still-wet fingers in alongside his tongue, and Charles' makes no sound at all but his eyes are squeezed closed and his mouth is hanging open and he's dragging in shallow, ragged breaths.

Erik lets up a little bit and, because it's there and because he's been thinking about doing this for-fucking-ever, he licks a long, sloppy stripe along the underside of Charles' cock in counterpoint to the rhythm of his fingers, and Charles' hand finds his shoulder and grips it so tight Erik winces, but doesn't stop. Charles shifts his hips restlessly, like he can't decide whether he wants to push back on Erik's fingers or fuck his mouth, and then he makes a noise like the indecision is killing him but that it would probably an awesome death.

And when Charles is good and wet and stretched, Erik fumbles one-handed at his zipper and manages to push his pants down to mid-thigh. Then he grabs Charles by the hips, and Charles locks his legs around Erik's waist, and he lines up, the head of his cock pressing against Charles' entrance, and then Charles is saying, "Wait, wait, you forgot –" and while Erik is briefly panicking, Charles spits into his hand with surprising delicacy.

And then he gets the hand between their bodies and curls it around Erik's cock and spreads the saliva around, while Erik's eyes flutter shut and he can't stop the desperate groan that leaves his mouth.

"We need to have a talk about the level of mutual touching in this relationship," Charles says, watching Erik's face like he never wants to look away. "But that's for later. Right now you need to stop pissing around and just fuck me already."

Erik drops his head onto Charles' shoulder and huffs out a laugh. "You are ridiculous," he says, into Charles' neck. "No one should sound this irritated in the middle of sex."

"If we hadn't stopped in the middle, maybe I wouldn't sound so irritated," Charles says, removing his hand, and, well, Erik supposes that's fair.

"Okay, okay, Jesus," Erik says, grinning despite himself, and he wraps his hands around Charles's hips again and pushes.

White noise drowns out whatever reply Charles might have had, and Erik sucks in a deep breath and tries to get past the immediate feelings of hot tight tight fuck hot perfect because he's going to come otherwise.

Charles makes a high-pitched, shocked noise and Erik manages to ask, "Hurts?"

"Yes," Charles gasps. "But – it's good, it's so good, Erik – don't you dare –"

Erik pulls out and slams back in, and Charles makes that noise again, and Erik reaches up to pin Charles' hands to the stairs, but Charles laces their fingers together and arches against him so that Erik drives in deeper, Charles' heel digging into the small of his back to urge him on.

Charles is making these lovely, breathy little moans as Erik fucks into him, and his cock keeps brushing Erik's stomach, leaving damp, slick trails behind, which sort of breaks Erik's brain in the best way. He's beyond any kind of coherency right now, but Erik knows he never wants this to end, he wants to break Charles open and carve his name on every cell of Charles' body, and he wants to do it forever, or at the very least, for the rest of their lives ...

He's unaware that he's saying most of this out loud until Charles makes a weird kind of hiccup and half-sobs, "Yes, anything, god, Erik, you –" and comes, hot and sticky between them. Erik is hit by a wave of pleasure that feels like a punch to the gut and shoves into Charles a few more times, and he manages to gasp out warningly, "I'm –" and then, "Charles," and then Erik completely falls apart.

It's a few seconds before he becomes aware of anything that isn't the result of what might just be the best orgasm of his life, and then he realises he's basically a dead weight on top of Charles and he pulls out, both of them hissing a little at the drag of skin. Then he rolls over so he and Charles are lying side by side on the stairs, panting and staring at the ceiling.

There's a brief silence and then Charles says, thoughtfully, "The stairs were probably a bad idea."

"The stairs were a fucking brilliant idea," Erik disagrees weakly, because it's the truth, but he just can't seem to get his breath back enough to make a more convincing argument.

"Yes, well, you're not the one with friction burns on your arse, are you?" Strangely, Charles doesn't seem particularly bothered about this.

"Let me see," Erik says, rolling him over and running his fingers over the red, slightly raised skin on Charles' ass. Charles shivers and curls an arm around Erik's neck.

"Really?" Erik says, incredulous.

"Apparently," Charles murmurs into Erik's collarbone.

"Okay," Erik says, reluctantly pulling away and standing up on unsteady legs. "Come on," he adds, holding a hand out to Charles, who takes it and pulls himself up.

They climb the stairs, shedding what little clothing they hadn't yet managed to get rid of, and stopping every now and then to make out like teenagers.

After all, they're both intelligent men. It's going to take some time for them to fuck each other stupid.

. . .

Sometime the next day, they're halfway through a lazy, mid-morning blow job when Mystique barges through the door.

"Charles, what the hell are your clothes doing all over the hall and – oh, Jesus, I did not need to see that!"

There's a brief silence, in which Erik tries to stifle a moan as Charles' mouth carries on doing exactly what it was before they were interrupted, and then Mystique says, in a carefully controlled voice, "I'm going to come back in ten minutes, and you'd both better be wearing pants."

She walks out, pointedly not looking at either of them.

Charles flicks a glance up at Erik, but doesn't say anything, his mouth being, as has already been mentioned, otherwise occupied.

"Don't you dare stop," Erik tells him, correctly interpreting his look. "Ten minutes, remember?"

True to her word, Mystique comes back, although she knocks first this time and enters the room with her eyes firmly shut.

"You can look now," Charles says, from where he's sitting cross-legged on the bed wearing a bathrobe.

Mystique opens one eye and then, seeing it's safe, opens the other.

"So," she says, looking from him to Erik, who's leaning against the headboard, also in a bathrobe and feeling a bit dazed. He hadn't thought it was possible to come half a dozen times in twelve hours but he and Charles had just spent the entire night proving how wrong he'd been to think so. "I'm guessing you two –" she makes a vaguely suggestive gesture with her hand.

"If by –" Charles copies the gesture "- you mean had incredibly satisfying sex, then," he turns to grin at Erik, who raises an eyebrow but can't stop the answering smirk, "yes. Yes we did."

"Ugh, I forgot how smug you are when you get laid," Mystique says, wrinkling her nose. "Whatever, I guess that explains the clothes all over the hall. It doesn't explain the blood, of course," she adds, eyeing them suspiciously. Erik wonders if she's checking them for wounds. "If it's some kinky sex thing, I'd really prefer it if you kept that to yourself –"

"Raven!" Charles yelps, embarrassed and blushing in a way that Erik suspects he will never stop being fascinated by.

"Oh," Mystique – or Raven, Erik supposes. Both names suit her, although he prefers Mystique – says to Charles, sounding amused now. "You finally got his name, did you? About time, I was wondering if that wasn't a sex thing as well."

"Oh, god," Charles groans, hiding his face.

"I had no idea, Charles," Erik says innocently, because at heart he's a bastard. "I can keep calling you Professor, if you like."

"Don't you bloody start," Charles gripes at him. "You've been here nearly two weeks and you only just asked my name yesterday, and then only because you wanted to sleep with me."

"Yeah, the boys told me they walked in on you the other day," Mystique laughs. "I think you've permanently damaged Alex – well," she adds, "more than he usually is, anyway. Havok," she says to Erik, "is a dick, but he means well. Mostly."

"He's really not that bad," Charles interjects. "Raven just doesn't like him because he keeps hitting on her."

"I never said I didn't like him," Mystique says, surprised. "I do like him, I'm just pissed at him because he and Hank keep having sex without me."

"Beast," Charles explains to Erik, and then, "Wait a second. What do you mean without you?"

Mystique raises an eyebrow at him, then says to Erik, "I hope you didn't give him a concussion while you were, uh, busy last night. He's not that bright at the best of times, if you keep banging away his brain cells –"

"Excuse me, I'm not an idiot, I am a professor, you know!" Charles protests, and both Mystique and Erik burst out laughing.

"Oh, god, Charles, you are so easy," Mystique grins. "In more ways than one," she goes on, staring pointedly at where Erik's hand has been slowly creeping along Charles' thigh for the past five minutes and Charles is tracing patterns on the back of Erik's hand absent-mindedly. They both pause in surprise; Erik hadn't even realised they'd been doing it.

"Um," Charles says, and Erik is close enough to see his eyes darken a little.

"Yes," Erik says carefully.

"Anyway," Mystique says loudly, "I'm going to go now, you two are clearly going to be impossible to be around. On the bright side," she adds suddenly, "now you've both finally pulled your heads out of your asses, you just won me fifty bucks, so I guess I can't be too mad at you."

"You were betting on whether Erik and I would have sex?" Charles splutters indignantly.

"Don't be ridiculous," Mystique says impatiently. "We were betting on when."

Charles makes an outraged sound as she turns to leave, but it quickly turns interested as Erik slides his hand under Charles' bathrobe. Charles rolls across the bed to get to him and is halfway through pushing the robe off his shoulders when Mystique pokes her head around the door again.

"I forgot to mention – oh, for the love of god, at least wait until I've left the room!"

"Go away, Raven!" Charles shouts, as he hooks a leg over Erik's hips and pushes their bodies together.

"I just wanted to say – I found a lead about who might be trying to kill you both."

"That's nice," Charles answers, clearly not listening to a word she's saying, and for good reason too – Erik's got a warm hand wrapped around his cock and is jerking him off as slowly as possible, just because he likes how foul-mouthed Charles is when he gets frustrated. "For fuck's sake, Erik, I'll do it myself if you don't –"

"Oh, god, I did not hear that, this is not happening," Erik hears Mystique complain in the background. "Charles, just – ah, fuck it. I'll leave you to it. If you hit your head again I'm not taking you to the emergency room, Charles!" and then, "Hey assholes! They're fucking like rabbits up here, pay up!"

This last comment is clearly directed to the boys, and Erik can hear a trio of distant voices make disappointed noises. He snorts but shakes his head when Charles looks at him questioningly.

"Nothing," he says, shoving their bathrobes away so he can see his hand on Charles' cock. "I think we've scarred her as much as we have – Alex?" he asks in confirmation. He's got a lot of new names to remember which is going to be difficult when Charles is occupying so much of his attention.

Charles nods. "Serves her right, she should have knocked. She's learned a valuable lesson today."

"Yes," Erik agrees. "For a start she learned you're a total slut."

"Oh, shut up, you love it," Charles says. He pushes Erik back against the headboard and straddles his hips, and Erik grins up at him.

"Yeah," he admits. "But only because you're a total slut for me."

(Which, as everyone knows, is emotionally stunted adult male-speak for I love you).