Title: Forty-Three Days.

Author: starjenni

Disclaimer: Not mine!

Characters, Pairings: Established Sherlock/John.

Warnings: Sex, serious UST (Unresolved Sexual Tension), swearing, violence.

Rating: T

Spoilers: All the episodes, I guess.

Summary: Sherlock doesn't have sex on a case. This one lasts six weeks (or forty-three days to be exact). UST abound!

They've been together not more than…oh, three weeks? John isn't the sort of person who counts the days that he's been in a relationship, and he is certain Sherlock is even further from that sort of person. But their last case was the Indecipherable Codes Case, and it was at the end of this case when everything changed, where something broke in both of them; it was at the end of this case when they began their…whatever this is.

And now, possibly three weeks later, although it could be more like two and a half, another case has arrived.

John greets this information with barely a grunt; it's been over a year that he's met and been sucked into his world, and yet somehow this extraordinary life has almost become…normal. He's also busy sorting out his work schedule for the week, so he misses the slightly nervous lilt to Sherlock's tone. In fact, he misses Sherlock's faint awkwardness throughout the whole evening, right up until he gets up to go to bed. It's barely ten, but he feels he needs an early night; it's been a week of both utter confusion and utter happiness, and he is exhausted.

"I'm to bed," he says, standing up. Sherlock, intent on his laptop screen, nods vaguely. They've spent nights apart since…well, frankly since they ended up in John's bed and did hardly any sleeping and only a bit of resting, and both seem to understand and respect this occasional need for space. But John thinks he should at least make some sort of sign of affection, so he leans forward to kiss him.

Sherlock scoots immediately backwards on his chair, hurriedly missing John's kiss, and then stares wide-eyed at him over his laptop.

John says falteringly, "Okay…". Oh god, he thinks. Don't let him be having second thoughts now.

"Um," says Sherlock, pale and suddenly radiating uneasiness. "There's, um. Something I need to say."

Sherlock never wavers, never stutters through his sentences. John's heart sinks involuntarily.

"Okay," he says again, trying not to sound too apprehensive.

Sherlock eyes him worriedly. "When I'm on a case," he says slowly, "I don't, um. I don't do anything else."

John frowns only for a split second, and then a light bulb goes off in his head. Of course, he thinks. He should have realised. "Like eating or sleeping," he states.

"Or sex," Sherlock adds promptly. "Or anything, really. No kissing or um. Anything. It's the case, it's just the case." He watches John apprehensively. "Is that," he says, sounding a bit lost. "Is that okay?"

Considering John was thinking that Sherlock was going to tell him he hated the sight of him, this is practically a relief. He struggles not to grin. "It's fine," he says easily. "It's all fine."

Six weeks later, it is anything but fine.

Week One

John's great until day four, he doesn't believe he even thinks about it very much. He vaguely misses Sherlock's presence in bed, but they are spending every day together so it's not so bad. Plus they haven't been lovers for very long, so he doesn't have to physically stop himself from kissing Sherlock at breakfast every morning or anything; it hasn't become a routine yet, what they've become, it is still being worked out. This is just like taking a step back, from lovers back into friends and flatmates. It's easy.

Or so he thinks, until day four, when they are visiting the crime scene for the second time, and Sherlock bends down in front of him to inspect a dusty footprint, and John suddenly finds himself thinking just how good that arse looks in those trousers.

Oh. Oh shit.

He tries to look away, but its too tempting a sight to ignore, and by the time Lestrade comes into the room, he is practically salivating.

"Are you all right?" Lestrade asks him; this is probably a fair question, John thinks, because he is standing by the door looking like he's just been hit with a hammer.

Sherlock glances at him carefully, halfway through surveying the state of the floorboards, and John swallows, feels his ears go hot with embarrassment and says, "Fine. I'm fine," and avoids Sherlock's stare.

John spends days five through to seven trying not to look at Sherlock too much.

Week Two

On day eight, in the evening, Sherlock comes out of his room in the disguise of a typical London clubber, which involves him wearing very tight and quite revealing clothing, and John has to lock himself in the bathroom until he is gone. Safe inside, he leans his forehead against the cool tiles of the wall and tells himself he can't, he can't, he must respect this wish of Sherlock's. Sherlock must have had problems with this before, with others he has been with and John needs to make this, as well as this whole…thing they have, as easy as possible for him.

He thinks about the tight leather trousers and asks himself again and again why he has to be so self-sacrificing.

On day ten, they collide quite by accident; John is coming out of the kitchen just as Sherlock is whirling in to check on an experiment, and they crash into each other halfway, and John's hands automatically fall to Sherlock's hips to steady him.

Sherlock sucks in a great breath of air, and John realises what he's done and drops his hands to his sides again. "Sorry," he mumbles. His pulse is going like the clappers.

Sherlock says nothing, and when John glances at him, he can see that there is a faint pink blush rising in his cheeks.

Looks like John isn't the only one having problems then.

On day thirteen (unlucky for some, John thinks that morning, grimly), they are taking a lift up an office building to the top floor, to interview a witness, and the lift gets progressively more and more crowded as they go. For the last ten floors, they are pressed together, chest to chest.

For once, John is glad that Sherlock is so much taller than him, because it means he can stare fixedly at the buttons of his shirt rather than at the man's face. Sherlock has his hands either side of John, bracing himself against the lift wall as they rattle upwards, and John feels in equal measures trapped and ridiculously aroused.

Buttons, he thinks, staring at them, but all he can think of is undoing them, and then sliding the shirt down those slim, pale shoulders and -

He coughs roughly, trying to break himself out of these thoughts, to think about something else, and sneaks a look up at Sherlock. Sherlock has his eyes closed, and something about the set of his jaw tells John that he is desperately trying to do the same thing. John is abruptly, horribly aware of everywhere Sherlock's body is touching John's; the side of his leg, the whole of his chest, even the brush of his arm against John's coat. It all burns, and he can't help but think about what he could do next, how he could take hold of Sherlock's face, tilt his head down, kiss him, right here, in the middle of everyone, and he can't, can't, can't.

The lift pings to indicate their floor and people start filing out and Sherlock leaps gratefully away from John as if he has just been given an electric shock.

They say nothing to each other.

Week Three

The case has already gone on far longer than any other case John has been with Sherlock on, and it is showing no signs of being completed, especially since their main suspect seems to be leading them a merry chase around London, giving everyone the slip. When they find him, John is going to throttle the man.

The smallest, lightest touches are the worst, because they are completely unexpected, and therefore more surprising and more arousing, and by day twenty-four, they are avoiding touching each other so much that the people who know them well are starting to give them funny looks.

On day twenty-six, Mrs Hudson asks John if they've had an argument, and offers to help them make it up to each other, despite John's gritted-teeth insistence that everything is fine.

Week Four

Now it has got so bad that Sherlock just being in John's viewpoint is driving him mad. He can't take his eyes off him though; he has taken to staring the man like an overly intent hawk, at everything he says and does, and knows he shouldn't, that it is probably annoying Sherlock just as much as it is confusing everyone else, that he is not being as sensible and mature or as patient and easy-going as he wanted to be, but god dammit

On day thirty he cracks, and he's not the only one.

"Just how long is this bloody case going to go on anyway?" he snarls when Sherlock mentions they have another line of inquiry to follow.

Sherlock doesn't look up from the papers strewn all over the kitchen table, but he does say, with a bite in his voice, "It would probably go a lot quicker if you didn't keep watching me."

"I can't help it!" John very nearly shouts in frustration, and Sherlock immediately snaps back, "You're distracting me," and they glare furiously at each other, case momentarily forgotten.

The temptation to haul Sherlock over the table and make him properly forget the case looms up threateningly in John's head, and he has to take a half-step back and breathe in deeply.

"Okay," he says. "Okay, what if I - " He passes a hand over his brow, suddenly feeling very tired. "What if I just didn't accompany you to any case stuff for a while? Would that help?"

He looks up at Sherlock; it's a bad mistake because at the mention of John not being with him, Sherlock's face falls in a ridiculously adorable fashion. If he says something like but I need you, John isn't going to be responsible for his actions.

This obviously shows in John's face, because Sherlock blinks very deliberately and then says, with false calm, "Fine."

Days thirty-one to thirty-four are spent by John in horrible, grey, devastating boredom, just like those before-Sherlock months, and by the time day thirty-five rolls around, he snaps and goes back on the case again.

Week Five

On day thirty-eight, there is a minor incident involving John and an unwieldy, unstable suspect, and he very nearly gets shot as a result of it; indeed, he might have actually got shot if he hadn't rolled away just as Sherlock brought the butt of his gun down on the suspect's head.

He lies on the floor for a moment, intent on getting up once he has caught his breath, but is saved the effort when Sherlock grabs him by his coat lapels, drags him into a sitting position and then proceeds to snog the living daylights out of him.

It is a clumsy, furious kiss, and it's so hot that it's practically painful. It's a clash of teeth on tongue and tongue on teeth, it's thirty-eight days without even a held hand, thirty-eight days of nothing, and John sinks hard and fast into it, all dignity or plans of restraint forgotten.

Five seconds later, Sherlock rips his mouth away and lets go of John's coat, dropping him back onto the floor again.

John stares up at the ceiling, battling to calm down his excruciatingly harsh breathing, all too aware that every vein feels like it is burning him from the inside. He tilts his head up, where Sherlock is kneeling with the side of a gloved hand stuffed firmly into his mouth and an agonised expression on his face.

"Sorry, I can't, I'm sorry," he says all in one breath over the glove.

John drops his head back to the floor again and contemplates murder.

Sherlock pulls his hand out of his mouth, and says a bit more coherently, "I didn't think, I just saw you were alive and I - I'm so sorry."

John thinks about saying it's fine but there really is no point in lying anymore.

"If you knew," Sherlock says haltingly, "What I want to do to you - "

"Sherlock," John says through gritted teeth. "Shut up. For god's sake, don't say anything more."

Sherlock wisely obeys him.

Of course, after day thirty-eight and the very stupid kiss, the whole situation just gets worse. John has been given a reminder of what he's been missing, a refresher, a taster of what he could quite easily have if he wasn't trying to be so damned respectful, and now he can't seem to think about anything else.

He has dreams where he can actually see the electricity, the chemistry between him and Sherlock, a thin, blazing, golden line connecting them together, and in the dream he can pull on the line, drag Sherlock towards him and do exactly what he wants to do, and when he wakes up he realises he can't after all, and bloody hell, bloody hell, it is driving him stark raving bonkers.

On day forty, it becomes Sherlock's longest case to date.

Week Six

On day forty-three, at about four in the morning, Sherlock catches the perpetrator finally, and he echoes John's sigh of relief as the police car takes him away, and they glance at each other and grin uncontainable grins.

Days forty-four to forty-seven are spent entirely in bed, in an electric black mess, in a silent hot void containing them and only them, and John burns up under Sherlock's fingers and tells himself in the intervening snatches of quiet that he is definitely the biggest masochist to exist ever.

He doesn't then tell himself that he doesn't give a damn, because he doesn't need to.

He knows it.