Dean Winchester and Sherlock Holmes: Two of the most difficult people to live with, never mind enduring a romantic relationship.

Also, to save any confusion: this takes place before "Doomsday" in the Doctor's timeline, after Season Two but before Season Three of Sherlock (because Season Three hadn't aired when I started writing this), and after Purgatory but before Season Eight of Supernatural because anything after Season Seven I'm pretending never happened.

"Dean."

Dean turned, frowning as Sherlock approached him. They had set out early that morning, and despite the hunter's rumbling stomach the Doctor didn't seem eager to stop for a lunch break any time soon - not now that they were so close to their goal. The lack of food and yet another long day on the road was not exactly helping Dean's mood, and now cheekbones wanted to talk to him?

At least Cas was cheerful, thanks to the sex last night, not needing to eat or sleep, and having that damn platypus to cuddle in his arms all day like a damn teddy bear. (That is, when John wasn't the one cuddling the damn platypus. Dean was pretty sure there'd be a fight over ownership before long.)

"What do you want?" He asked, possibly a bit more irritated then the situation warranted.

"I just wanted to ask you a few questions," Sherlock responded conversationally.

That pinged a few alarm bells. Sherlock was never one for conversation.

"What about?" Dean asked, suspicious.

"You and your angel there," Sherlock said.

"He has a name."

"Castiel. You and him. How did you…?"

Dean frowned. "You wouldn't really believe it if I told you."

Sherlock's gaze was challenging. "Try me."

Dean sighed. "He yanked me out of Hell," He explained.

Sherlock looked… well, Dean would say confused, but Sherlock never looked confused.

"And you dated him because of that?"

Dean blinked. "What? No! That's how we met!"

"Oh." Sherlock looked very much like he was trying not to roll his eyes. "How did you two become a couple, then?"

"Uh…" Dean cleared his throat and glanced at the others up ahead. Cas was animatedly explaining the Garden of Eden to an enraptured John Watson, while Sam and the Doctor were arguing over some aspect of the zombie reversal spell that Dean wasn't even going to try understanding. None of them, fortunately, appeared to be paying attention to his conversation with Sherlock.

"It was, um, a few months back actually. We've known each other a long time, Cas and me. Been through a lot together." Dean cleared his throat again. "But then we… well, we got into a situation I didn't think either of us would live through."

"What kind of situation?"

"You wouldn't believe me."

Sherlock made an exasperated noise. "I shall be the judge of whether I am capable of believing something or not."

Dean rolled his eyes. "Right. We were in Purgatory, okay? Monsters everywhere, no food or sleep or shelter anywhere. No choice but to keep fighting. And I thought, we weren't gonna get out. We were gonna be stuck in there forever, or we were gonna die there. And I thought… well, fuck it. Who's gonna judge us? When am I gonna get another chance?"

"So you confessed your feelings?" Sherlock asked.

Dean felt his neck heating up. Could someone remind him why was he telling all of this to the consulting prick? "Not exactly- I mean, I did, just not at first. We were, uh, well let's just say Cas nearly bit the dust. I panicked a little and, uh, planted one on him."

Sherlock raised his eyebrows. "You kissed him?"

Dean cleared his throat. "Um, yeah, well. He kissed back, okay? And after that it was just… it was like the missing puzzle piece fell into place."

Sherlock appeared to be contemplating this. "I see."

"Great. Glad to hear it," Dean snarked. "Now we are moving on and never discussing this again, got it?"

Sherlock didn't even seem to be listening to him anymore. Dean gave a growl of frustration and hurried to catch up to Cas. He slung an arm around his angel's shoulders, which earned him a confused look from Cas before the angel continued on with his story.

"…and so Lilith fell and became the first true demon. Not a fallen angel, made demon on their own, but turned into one by Lucifer. His first real creation, if you can call it that. And so God created a new woman, this time from Adam's rib, thinking that if she was a part of Adam then she would not turn from him as Lilith had…"

Dean grinned. Yeah. Might have been awkward as hell at first but he wouldn't trade what he had with Cas for anything.

The group stared up at the ruined castle, collectively frowning.

"Well, leave it to the guy to be all dramatic about it," Dean noted.

"Are we seriously going to try and storm the gates?" John asked.

"My powers have somehow been nullified in regards to this place and the spell Crowley cast," Castiel explained. "But if Sam and the Doctor's information is correct…"

Sam held on the piece of paper on which they'd scribbled down the reversal spell. "I think it should work," He said, squinting at it. "Although the Doctor's writing is terrible."

"You try writing in English when it's not your first language," The Doctor sniped back.

"Let me see that," Sherlock insisted, snatching the paper.

"Not so fast, boys," A Scottish voice drawled.

Dean rolled his eyes. "Always with the dramatic entrances?" He asked as they turned to face Crowley.

Watson frowned. "This is a demon?"

"King of Hell, if you please," Crowley rebuked. "And really, you'd have thought my bottling up angel boy's powers would have been enough of a deterrent for you."

"A zombie apocalypse, though…" The Doctor said contemplatively. "Doesn't seem particularly clever."

"The spell didn't exactly do what I thought it would. False advertising," Crowley explained.

"Oh for the love of God are we going to stand around discussing this or are we actually going to get around to the villainous monologue anytime soon?" Sherlock snapped, annoyed. "I would like to hurry this up and take a proper shower."

John muttered something, but nobody could hear exactly what it was. Judging by his tone, it was something about Sherlock, and it was none too flattering.

"Right, if you insist," Crowley said. "Would you like the classic It's-Too-Late-You-Can't-Stop-Me, or something more in the vein of If-I-Go-Down-I'm-Taking-You-With-Me?"

"Are those our only two choices?" Sam asked.

"Oh, Moose," Crowley clucked his tongue. "So picky."

"How about…" The Doctor whipped out his sonic screwdriver and brandished it threateningly. "I just threaten you with this!"

Crowley's forehead furrowed in confusion. "What is that? A laser pointer?"

The Doctor gawked at him. "Unbelievable! Unbelievable. You people…"

Sherlock, meanwhile, had been reading the spell over Sam's shoulder. "You've got that part wrong," He noted.

Sam glanced up at him. "What?"

Sherlock pointed. "That. Right there. Completely illogical given the sequence of the intonations."

Sam blinked, and then handed the spell over. Sherlock immediately began scribbling away.

"I don't understand," Castiel said slowly. "Why does there need to be a villainous monologue?"

"Tradition, Cas," Dean explained.

Castiel considered this, and then nodded acceptingly.

"Right. Epic final battle time, or…?" The Doctor asked.

"I still haven't gotten my monologue yet," Crowley objected.

"Got it!" Sherlock announced, handing the paper back to Sam.

"This makes no sense," Sam said, squinting at the atrocious handwriting.

"Of course it does," Sherlock pointed at the paper. "Sirius Mundi…"

"All right!" John bellowed.

Everyone fell silent. John gestured at Sam. "If you please?"

Sam sighed, and began reciting the incantation.

"Bullocks," Crowley muttered. "Is this my queue to pop off then?"

"Actually the spell will send you back to Hell in about ten seconds," Sherlock said. "If Sam recites it properly."

"Sam's been reciting Latin since he was five, I think we're good," Dean snarked, glaring at Sherlock.

"'Til next time, then," Crowley said with a sigh as he vanished.

When Sam finished the incantation, there was a very long pause as everyone looked around. Other than Crowley's vanishing act, there was no sign that the spell had worked.

"How do we know the world's not still battling the undead?" John inquired.

"Good question," The Doctor noted.

"Does this mean we can't keep Irwin anymore?" Castiel asked, clutching the platypus tightly to his chest.

Dean sighed. "We'll talk."

Sherlock's phone rang. The detective looked at the caller ID, sighed dramatically, and handed it to John. John rolled his eyes and answered it.

"Hello, Mycroft."

There was a pause as Mycroft spoke at the other end. John covered the receiver and spoke to the others. "He says that the zombies have mysteriously vanished but because of that so has the majority of earth's population. Yes! Yes I'm listening." John frowned. "Mm-hmm. Yes, he's here." John turned to the Doctor. "He says they're sending a helicopter for you, it's been an annoyingly long time, and there's a demanding blonde giving everyone orders who is coming to pick you up."

"How did they know where we were?" Sam asked.

"Mycroft does that," Sherlock said, bored.

A breeze sprung up, blowing the grass about as a helicopter came into view. "That was quick," Dean observed.

John, meanwhile, had started arguing with Mycroft over the ethics of his lack of action during the zombie apocalypse. "It took a girl barely into her twenties to get anything done, and now that it's over you manage to not only locate us but send a helicopter within five minutes!?" The former army medic bellowed.

"I think he gets the point, John, he was a terrible human being again, business as usual," Sherlock drawled, taking the phone from John and ending the call.

"This is a serious matter," Castiel said, sounding distressed. "Do we have to give Irwin back to the zoo or not?"

"We'll talk in a sec, Cas," Dean said soothingly.

They all watched as the helicopter banked low, circling one more time before it came to rest on the grass about fifty feet away. The door opened and someone exited: a petite, female someone, with blonde hair, warm brown eyes, and the biggest grin on her face. She was dressed in the same outfit as when the Doctor had last seen her, and she was carrying a mighty large gun.

The Doctor started running.

"Who is that?" Castiel asked.

John grinned. "I'm willing to bet that's Rose Tyler."

Rose was sprinting as fast as she could, the gun banging against her body in a rather painful manner but she didn't care, didn't even notice, as she reached the Doctor. She dropped the gun.

It went off with a massive bang.

Every single person jumped and drew their weapons before they realized what had happened.

"If it isn't you giving me a heart attack," Dean muttered to Cas, "It's something."

Rose shrugged. "Sorry?" She said, not sounding sorry at all.

The Doctor swept her up into a hug, squeezing the air out of her, mashing her face into the crook of his neck.

It was extremely uncomfortable.

She didn't give a damn.

Well, except for the not being able to breathe part. That needed fixing.

Rose pulled back, smiling up at the Doctor, who was positively beaming. "Knew you'd find a way to fix it," She told him.

"And you managed to keep the government running," The Doctor replied, spinning her around. "Rose Tyler, Zombie Resistance Leader."

She laughed, but as he stopped spinning her the laugh died away, leaving them still holding each other, faces mere inches apart, staring.

Sam leaned over to the others. "I think this is the part where we look away now," He whispered.

Sure enough, the Doctor leaned down and kissed Rose fiercely. She responded in kind, gripping him tightly and opening her mouth with a contented sigh.

"I thought you were dead," The Doctor explained, his voice hushed.

Rose tightened her grip on him, brushing her lips against his. "Take more than a few zombies to keep me from you," She teased. "Not even a parallel universe could stop me. All of time and space, you promised me, and I aim to make you keep that promise."

The Doctor kissed her again, and then tugged on her hand. "Come on," He said. "There are some people I want you to meet."

Rose took an immediate liking to Sam, Dean and John, thought Castiel was awkward but adorable, and had an interesting few moments with Sherlock before they both decided that they could respect each other, but they never wanted to speak to one another ever again.

They all took the helicopter back to London, where the TARDIS and Sherlock and John's flat awaited them. Mycroft gave them all a thorough debriefing (he and the Winchesters immediately hated each other, although Castiel earned points with Sherlock for being the first thing to completely baffle Mycroft Holmes), and then it was time to go their separate ways.

"Take good care of him," Castiel intoned as he handed Irwin to Watson.

"You know the only reason we're keeping that little creature is because you hid my skull," Sherlock noted.

"Of course, Sherlock," John replied. "That's why I caught you petting him while he was napping yesterday."

"I was n-!"

"Lovely to have met you all," The Doctor said quickly. "But we really should get going."

He and Rose shook hands with everyone, Dean warning him that he had "quite a catch there - better take good care of her" and jerking his head at Rose. The couple then headed back to the TARDIS.

"Cas?" Dean said with a grin. "Think you can zap us back home?"

Castiel nodded, giving Irwin a final pat on the head. "Be good," He warned the platypus seriously.

Irwin made a purring sound.

Castiel placed a hand on Dean and Sam's shoulders, and in a blink they were gone.

Leaving John and Sherlock alone for the first time in several days.

Sherlock cleared his throat. "Shall we walk back?" He asked.

John shrugged. "It's certainly nice enough out."

"And not as many people," Sherlock noted. "Won't be too crowded, now that the planet's population is down to about a hundred million."

John tried to suppress a chuckle and failed. "That's not funny, Sherlock."

Sherlock merely smirked.

They made their way through nearly-deserted London, John occupying himself with taking in the destruction and handling Irwin. After about ten minutes of tense silence, Sherlock cleared his throat.

"I had an interesting conversation with Dean Winchester yesterday morning."

"Did you?" John said mildly, only half listening.

"Yes," Sherlock stopped walking. "He said that he and Castiel, the angel - if he really is an angel-"

"He disappeared into thin air, Sherlock."

Sherlock waved that fact away. "In any case, he said that he had admitted his feelings to Castiel after they were in a life or death situation, one that he was afraid they couldn't get out of."

John nodded. "Makes sense."

"I am not one for choosing a dramatic moment," Sherlock began.

"Yes, you are," John retorted. "You're the worst drama queen I know."

"John, would you please let me finish?"

"What's the point of this anyway?" John asked, frustrated. "You go off at me a few days ago, you barely speak to me after that, and now the whole thing's over you want to suddenly chat about Dean Winchester - who, by the way, you hate - and his relationships, and feelings, which you never do, and-"

"John!" Sherlock shouted. "Has it occurred to you that I am trying to apologize for my actions the other day and tell you that I was angry because I was scared you would go and die without me because I love you?"

There was a rather long pause after that declaration. John positively gaped at Sherlock. "You… you what?"

Sherlock looked incredibly pained. "Please don't make me embarrass myself twice in a row," He said quietly.

"You… you. Sherlock Holmes. Married to his work Sherlock Holmes. You're…?" John appeared incapable of completing a sentence.

"Yes."

"For how long?"

"Since the pool."

John heaved a sigh, and Sherlock looked down at the ground, certain that it was over. John would ask to move out, and he'd take the damn adorable platypus with him, and-

"You sodding idiot. Why didn't you say anything sooner?"

And then they were kissing in the middle of an empty London street, Irwin the platypus squished between them.

Rose would like to start out by saying that she was all for sex, especially hurry-we're-not-dead reunion sex. However, she would like to add that sex on the floor of the TARDIS is far from the most comfortable thing she'd ever experienced.

It's the floor vents. They leave marks.

Still, she wasn't complaining. They'd started making out the second the TARDIS doors had closed behind them and they hadn't really stopped until they'd needed to separate so that they could pull each other's clothes off. She definitely wasn't complaining about being able to finally touch what she'd been fantasizing about all of these months, getting to take the Doctor apart with her hands and her mouth. And she most certainly wasn't complaining about his bedroom skills.

Apparently it was possible to orgasm three times in the space of forty-five minutes. Who knew?

They were still lying there, a tangle of limbs and discarded clothing, when Rose's phone rang. She rolled over onto her stomach, groaning, and fumbled about until she had wrestled the annoying device out of her pocket.

"Tell them to bugger off," The Doctor said, shifting to wrap an arm around her back and burying his face into her hair.

"It's Mum," She said, making a face. "Sorry."

The Doctor said something in Galifreyan that Rose had learned, over time, roughly translated into "fuck".

"Hi, Mum!" Rose said, faking cheerfulness.

"Where the bloody hell have you been!?" Jackie Tyler's voice came out loud enough for the Doctor to hear. "First I don't know where you are, and then you're the leader of some Zombie Resistance, and then next I hear you've popped up to Scotland! You couldn't have thought to check up on your mother through all of this? Make sure I'm not a Walker?"

"I'm sorry," Rose said apologetically. "The Doctor's been through a lot, is all…"

"So the Doctor is suddenly more important than your mother?" Jackie said, pulling an affronted tone. "I need help recovering too!"

The Doctor buried his face into Rose's shoulder to muffle his laughter.

"Yeah, but Mum…"

"I'm going to need to recover from the recovering," The Doctor whispered in Rose's ear. She planted her hand on his face and pushed him away a little.

"Look, Mum, I'll be there soon, yeah? Just make yourself some tea or something."

"Tea? I've just dealt with an army of bleedin' corpses and you're telling me to sit and make tea while you nurse your precious Doctor!?"

Said Doctor was finding the spot of skin just below Rose's ear fascinating, and was exploring it thoroughly with his tongue.

"I seriously have to go, Mum! See you soon!" Rose quickly hung up and rotated so that she and the Doctor were face to face. "You," She warned him, "Are incorrigible."

The Doctor grinned. "I've just been through a zombie apocalypse, Rose," He said. "I'm in shock. Can't be held responsible for my behavior."

Rose's lips quirked upwards. "I guess I'll just have to help you recover, then," She said, her tongue poking out from between her teeth as she smiled coyly.

"Might have to go through several recovery sessions. It was quite a traumatic time," The Doctor warned her.

Rose laughed. "Oh, there'll be recovering all over the place. But this time on the bed."

She shoved him towards the hallway that led to the TARDIS's other rooms, laughing when he scooped her up instead and carried her, her giggles echoing throughout the immense ship.

The TARDIS hummed, glad that those two had finally taken that final step. If dropping them in the middle of the apocalypse hadn't worked the ship would have been forced to lock them in a room together.

"Goodbye, England. Helloooo, good old U.S.A." Dean grinned, stretching his arms up over his head until his shoulders popped. "There you are, Baby."

The Impala was sitting right where they'd left it, a bit of dust on her windshield but otherwise in perfect condition. Dean hurried over, running his hand over the hood lovingly.

Sam was a bit more out of sorts, grumbling unintelligibly to himself as he folded his lanky body into the front passenger seat.

"Are you all right, Sam?" Castiel asked.

"Ah, ignore him," Dean said, wrapping an arm around the angel's waist. "He's just cranky 'cause he couldn't get laid during a freakin' apocalypse."

"Can you just get in and drive?" Sam groused, pulling Bitchface #39.

Dean grinned, slipping behind the wheel as Cas settled into the backseat. "All right, boys." He said. "Let's go."

"Where?" Castiel asked.

"The nearest diner. I need a fucking pie. And a beer."

"Dean, the level of alcohol that you consume is not…"

"Cas, I'm fine. My liver is not going to explode."

"No, it will merely shut down."

"Son of a bitch, Cas, could–"

Sam cranked the radio up as high as it would go, trying to tune out the sound of an argument that probably wouldn't stop anytime soon.

The Impala roared off into the sunset.

"Lestrade," Sherlock said with a nod. "Good to see you had the brains to survive."

"Pun not intended, I assume?" Inspector Lestrade said with a sigh. "Should've known you'd make it out."

"I'm impressed," John said, looking around. "Hardly a week after the whole thing and already the Yard is back on track."

"Maybe we're not as incompetent as Mr. Holmes would like to believe," Came an annoyingly snarky voice.

Anderson strode over, tired-looking but otherwise fine.

Sherlock made an annoyed sound. "Just my luck. Ah, well. Can't have everything, I suppose."

At Anderson's look of complete incomprehension, John began a coughing fit to hide his laughter.

Sherlock didn't bother hiding his smile.

And there you have it folks! You know, this was supposed to be a fun, cracky little thing I wrote and it turned around and gave me more trouble than the rest of my stories combined. Ugh. I hope you all enjoyed it, and feel free to leave a review!