Introspect

It is an accident the first time.

Erik Lehnsherr never does things by halves, but the first time he propels some rather explicit thoughts in Charles's direction, it is completely unintentional.

Charles is walking down the hallway the first time it happens – fresh out of the shower, with a bathrobe wrapped loosely around his slender frame as he pads through the regal vestibule of the mansion, from the bathroom to his own bedroom. Erik only needs to retrieve something from his room, completely innocent, as he rounds the corner to be greeted by Charles; his hair still damp, the robe clinging to his sodden torso. He almost can't control himself, there and then. Charles, of course, is none-the-wiser of Erik's internal battle, and upon spotting his friend, nudges a friendly 'hello there, Erik," in his direction with a smile. Erik tries to smile back, but his face just curls into a smirk.

Charles Xavier has the ability to read minds by choice – by targeting a specific person and delving into the deep folds of their brains. But every so often, he can't control what he hears. He and Erik had come to an agreement a long time ago that Charles would never intrude in Erik's mind unless absolutely necessary, and the professor had no intentions of breaking that rule. But Erik's mind, on this occasion, decided it is going to be louder than either of them anticipated.

So when Charles smiles at Erik that morning, Erik's mind decides to think back: 'I'd love to see what's under the robe'.

Erik personally is used to these kinds of thoughts about Charles, so it isn't a rarity for him. But as he watches the professor's brow crinkle – not exactly in horror, but more in shock – he knows something has gone wrong.

He opens his mouth to say something, but Charles just smiles again, a little timidly, and scurries off down the hallway.

He doesn't see him again for the rest of the morning.

The second time it happens wasn't exactly on purpose, but Erik knows what he is doing – and he knows Charles is listening.

The four teenagers are all seated at the table in the mansion's rather large and expansive kitchen, squabbling over leftovers as they help themselves to a small buffet of sandwiches and cakes that Charles had decided to put out for them. Charles himself is leaning against one of the kitchen counters, a cup of coffee in his hand as he watches the children fondly; they are his work in progress, teaching them how to harness their powers.

Erik chooses that moment to appear in the doorway, and leans against the frame. He looks at the four of them for a moment; Sean and Alex bickering over a cheese and ham sandwich, while Hank holds one of the plates over towards Raven so she can get the first pick – and then his eyes saunter over to Charles, bundled up in one of his cardigans with a frankly adorable smile across his face.

The metal-bender waits until Charles lifts the coffee mug to his lips to project his thoughts towards him again: wouldn't mind bending you over that table when the kids are gone.

Charles coughs and splutters, sending a spray of coffee across the room. The mutants at the table stop their arguing and turn to look at their professor, each of their faces the very epitome of confusion.

"Are you alright, Charles?" Raven asks, her brow furrowed.

"Yes," he nods, his voice as little hoarse as he wipes the remaining droplets of coffee from around his mouth, "Yes, yes, I'm fine."

Erik is still smirking in the corner when they return to their meal, and he grins when Charles turns to glare at him.

It is a game now. Not so much a game with a winner and a loser, but more of a 'let's see how long it takes for Charles Xavier to finally crack' kind of game. Erik can't pretend he isn't enjoying himself.

One of the more notable times that he forces his thoughts on to Charles is when the telepath is just finishing one of his runs with Hank. Erik is waiting at front of the house, toeing at the gravel beneath his feet as he leans on the stone wall of the balcony and looks out over the gardens. It doesn't take him long to hear the crunching of the gravel as Hank and Charles round the corner, both of them panting and sweaty – and that alone is enough to start Erik's mind whirring.

"Good job today, Hank. You're improving rapidly, my friend," Charles manages to get out, his breathing uneven as he claps the young scientist on the back.

"Thanks, professor," Hank smiles. "Actually, I was wondering if you would teach me a little more about the mutations this afternoon. I have a basic understanding but... it makes sense to hear it from the best of the best," he chuckles. Charles nods enthusiastically.

"Of course, of course. What exactly did you want to know?"

"How they form... how they adapt... everything."

"I see. Well, the formation is very basic. Sometimes it's hereditary so it all depends on the genetics of the parents. During conception, sometimes the genes can get a little scrambled and they can-"

Erik decides that now is as good a time as any to project not a phrase this time, but an image. He leans sideways against the balcony as he smiles slyly over at Charles, feeding him thought after thought of the professor on his knees in front of the metal-bender, and then a picture of Charles bending over the very balcony he is leaning against.

"Ch-Charles?" Hank asks, his brow furrowed as he looks at the telepath, whose face has grown rather pale despite his flushing cheeks.

"Uh... I think we'll continue this in the afternoon, like you said. I need some water first," he nods, pursing his lips together. Hank smiles briefly before excusing himself and shuffles back into the mansion. Charles snaps his head towards Erik, who is fondly stroking the side of the balcony, as if beckoning him. "You need to stop it," he mutters as he walks over.

"I don't know what you're talking about." Erik shrugs, running a hand through his hair.

"You know exactly what I'm talking about, Lehnsherr. Stop it. Right now. The children think I'm going crazy. I think I'm going crazy," he chastises, using his teacher voice now.

"Crazy about me." Erik mutters under his breath, although he knows Charles can hear him, and he raises an eyebrow in his direction. Charles just sighs.

"Just cut it out," he says sternly, pinching the bridge of his nose as he walks back towards the mansion.

Erik projects another image of Charles on his knees, just to be sure.

"You sure you're ready?" Raven asks as she lowers the Cerebro helmet onto Charles's head.

"Of course I am. I found all of the others this way, didn't I? ... I'm sure we'll be fine," the telepath nods, holding onto the bars in front of him. "Go on, Hank. Turn it on."

All six of them are stood in the strange metal room; Charles is the pinnacle of all the attention, as he stands in the centre of the room; Raven is stood right beside him, although he beckons her to move away so he can begin; Erik has stationed himself in the corner near the exit, almost hiding in the shadows, but still very present; Hank is poised by the control panel; and Sean and Alex are nudging each other and chuckling – they probably have a bet on about who the next mutant will be.

"Stop it," Erik huffs, in an almost baritone articulation, his first words since entering the room – making his presence known. That shuts the pair of them up pretty quickly – they aren't afraid of Erik, but if they see Charles as a doting motherly figure, then that makes Erik a much harsher father by comparison.

Once the room is silent apart from the gentle humming of the machinery, Hank pushes the main switch forward and fiddles with a few of the buttons on the controls. Charles inhales a sharp breath as his mind is surged forward into a new world – he can see mutants from miles around, lighting up like a Christmas tree. He can see them both individually and as a whole, like a flock of birds flying in a murmuration across the sky. There are young boys and girls whose powers are unknown to themselves yet, and elderly men and women whose time to do something good with their mutations is almost up. It is a quick insight to life and death; as Charles watches new mutants being born, and old ones slipping away. He is completely lost in this universe of people, his mind flitting from mutant to mutant, assessing their powers and seeing which ones would need the most help. But despite being so heavily preoccupied, there is something niggling at the back of his mind.

Cerebro acts as an amplifier – he can see mutants as if they are on a huge television screen, their thoughts and feelings intensified for him and only him to see. But even though he can see this entire cosmos of the populace, he finds himself drawn to the thoughts of someone in that very room. Even when he is lost in an abundance of other people, his mind will still respond to Erik's every whim.

I could take you now, y'know, the metal-bender thinks at him, I could just stand behind you and rut against you and make you feel things you've never felt before. I could fuck you into oblivion time and time again and you'd still come running back, wouldn't you?

Charles tightens his grip on the metal bar in front of him, his knuckles turning white. The metal-bender's thoughts are displayed on the Cerebro screens; he can't do anything but see it, and hear it... and feel it. He keeps his breathing even and tries to ignore Erik, but it's not an easy task – he's so used to it being the other way around, people blocking out the telepath, not the telepath blocking out the people.

You'd love it, wouldn't you? I could bend that metal bar you're holding so it tied around your wrists and kept you in place for me... I could stand behind you right now and kiss your neck, my hands all over your body. We could make the others watch. Wouldn't that make you feel dirty?

Just focus on the mutants, Charles. Mutants. Mutants.

The final straw is when Erik transmits an image of what he's been describing – himself stood behind Charles with his hands digging into his hips, biting up and down his neck while the telepath himself is held in place, with no escape... just letting Erik have his wicked way.

"Turn it off!" Charles bellows, his eyes snapping open; his pupils are dilated as he pants heavily, a soft sheen of sweat forming on his brow as the room erupts into panic. Hank does as he is told and quickly turns the device off, while Raven moves to remove the helmet from Charles's head. His whole body goes weak and he almost collapses there and then – trying so hard to fight off Erik's thoughts has made his legs turn to jelly.

"Jesus, what happened?" Raven asks, her eyes bright with alarm as she puts an arm around Charles to support him. "What did you see?" She begins to lead him out of the machine, still bombarding him with questions, but as they walk out, they pass Erik leaning against the wall.

Charles looks at him; eyes half-lidded, lips parted. Erik just grins, biting his lip gently, and says aloud: "Yes, Charles, what did you see?"

It goes on like this for just over a week; Erik projecting thought after thought in Charles's direction, and no matter how hard he tries to block him out, Charles is useless to the man's advances. It shouldn't be this hard – he's a telepath. Mental shields are his specialty. Blocking people out should be simple... but Charles is beginning to think that perhaps the reason his mind refuses to ignore Erik's calling is because he's enjoying it.

He looks forward to it; at least once or twice a day, Erik gives him something to think about, and Charles relishes the thought. He's past the stage of blushing uncontrollably like a schoolgirl, and now he almost welcomes the thoughts Erik provides him with – although he'd never admit that to the metal-bender himself. He still glares at Erik when he sees him, and he tells him that it's 'very inappropriate' in his best teacher voice – but he gets the feeling that both of them know he's bluffing.

It all comes to a head when the pair of them are sat in the drawing room rather late at night after all the children have gone to bed; a chess board between them and a glass of scotch in each of their hands. Charles is surveying the board and considering where to make his next move when Erik sends him a rather clear image of them in a compromising position.

Charles is sprawled on his back with Erik between his legs; the professor's face completely blessed out while Erik has a hand in his hair, tugging gently as he kisses up the man's jaw line, moan after muffled moan escaping from both of them as the metal-bender thrusts slowly into Charles's body.

Well, it's a little more romantic than some of the other images he's had.

Charles finally settles on moving his bishop diagonally to the left, claiming one of Erik's pawns in the process, and keeps a poker-face so Erik doesn't know he's received his little message.

Erik knows. He can read Charles like a book – and he can see from the slight quirk of Charles's mouth that he's seen the image he gave him. But hey, if he wants to play it like that, it's not too hard for Erik to conjure up another one. Within seconds, he's sending Charles an image of them against a wall – Charles's legs wrapped around Erik's waist as the other man thrusts in to him, Erik's hands planted firmly on to Charles hips while the professor's own arms are looped around Erik's neck as they kiss passionately.

"Oh please. It wouldn't be like that," Charles finally speaks up as he takes a sip from his scotch glass. Erik smirks crudely and raises an eyebrow.

"Wouldn't it? ... Then how would it be?"

With all of his teasing, Erik has almost forgotten that Charles is the telepath here – so it nearly comes as a shock when Charles is suddenly in his head, feeding him the dirty thoughts.

There's one of Charles on his knees with his head between Erik's legs, looking up at him with a smirk on his face. There's an image of Charles grabbing Erik by the front of his turtleneck and kissing him harshly. And there's one of Charles straddling Erik's hips; his head thrown back with pleasure; his fingernails digging sharply into Erik's shoulders as he rides him.

Charles grins to himself when he sees Erik's face – taken aback by the professor's audacity, although undeniably turned on by the whole ordeal.

"You don't like having a taste of your own medicine, do you, Erik?" Charles smirks as he leans back in his chair, observing the man carefully. It takes Erik a few moments to respond, as there isn't much blood in his head anymore.

"I know what I'd rather have a taste of," he finally retorts, and that dirty smirk is back on his face. This time, Charles finds himself returning his grin, and before he can register what he's doing, he's up from the armchair and has moved to seat himself in Erik's lap – just like in the thoughts he has sent him. He wastes no time in putting one hand in Erik's hair, smiling when he feels the man's arms wrapping around his waist, and grabs the front of Erik's turtleneck to pull him into a bruising kiss.

It's better than either of them imagined.

Two days later, they finally tumble into the sheets of Charles's bed after having relentless nonstop sex in every possible position, in every room in Xavier mansion – and that's a lot of rooms.

"You could have just told me you wanted to sleep with me." Charles sighs softly as he lies on top of Erik's chest, playing fondly with a rogue lock of the man's hair.

"Ah yes, that will have gone down well. 'Hello there, Charles. Good morning children. I have an announcement to make. I want to screw your professor until he can't walk anymore. Have a nice breakfast.'" Erik huffs, although he is smiling fondly.

"You know what I mean," Xavier smiles, resting his chin on Erik's chest to look up at him as he traces little patterns on the man's skin with his finger. Erik chuckles to himself and puts his hand underneath Charles's chin, pulling him forwards to kiss him again, and hums into his mouth gently. "Ready to go again yet?"

Erik grins and bites his lip. "I like your thinking, professor."

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