[Warnings: Disturbing imagery, violence, dark themes, mild breathplay]
"Just because you're a monster," Harry whispered to him late one night, "doesn't mean you have to act like one."
They were too young and too honest; they quickly learned better. But John remembered those words. His parents always talked about Harry, problem child. She was loud, angry, brash. John was quiet, smart, affable. No need for further examination. John was the good one.
He never had the heart to tell them how wrong they were.
There was affection enough for his family-he knew those ties meant something. But when his father contracted Alzheimer's and turned into a stranger, John was unmoved when he died. As Harry fell into the bottle at twenty-six and never quite got out of it, slowly destroyed everything good in her life, John felt only irritation.
.
John knew something was wrong, that he wasn't supposed to be this numb. But perhaps if he tried hard enough, he'd learn to care more. So he went to medical school and lost himself in anatomy.
.
The first time he helped with a birth, he got to hold a newborn baby in his hands.
All he could think about was how fragile, how breakable it was. Tiny bones, tiny lungs, the skull an incomplete shield. Just the smallest exertion of pressure, and—
He called out sick the rest of the day.
.
Six years, and no luck. He joined the army, trying to find a purpose, to make his lack of investment have some sort of meaning. Death lurking around the corner didn't seem like a bad thing.
.
The first time he fired a gun, he hit the target in the head at 20 feet. There was laughing, talk of beginner's luck. Then he did it again. And again at 30. And again at 50. Jaws were slack, eyes shifting uncomfortably.
He was pulled aside, asked again if he'd ever fired one before.
He hadn't touched one, (he knew what he'd do.) They didn't believe him.
John wondered what it meant, that he had to study hours and hours to pass his medical exams, but the gun felt natural in his hand.
.
A man in a suit with a false smile came to talk to him. Asked if he has ever considered intelligence work, asked how far he'd go to serve queen and country.
"I'm a doctor," John insisted, wondering who he was trying to convince more.
The man left and John hoped that that was the end of it.
.
John found himself in the field far more than an army doctor should be. He loved it. He knew he shouldn't, knew the noise and death were exactly what he should avoid, but he was good at it.
It was hard not to stop, to watch, fascinated, when the spark that made people faded and they became sacks of meat and bone. Funny how much harder it was to save than to take away.
When he found himself hard after choking a man and snapping his neck, when he looked at the blood spatter on the clothes of an injured soldier and thought beautiful, he knew something had gone very, very wrong.
It was almost a relief, being shot. Somebody stopped him before it was too late.
.
Harry remembered everything despite her attempts to pickle it in alcohol. They met face to face for the first time in eight years, John weak from recovery and confined to his hospital bed.
She flinched when their hands brushed over the phone. Her mouth said "Keep in touch," her but her gift, her eyes said, "Keep your distance."
.
"I have an assignment for you," the man with the suit said as he twirled his umbrella.
"I'm invalided out; I'm not a soldier anymore." John didn't quite succeed at not making it sound bitter.
"Nothing that would compromise your morals, Dr Watson," he said like it was a little joke between them. "Just watching over a particularly difficult man. He does rather like to get himself into trouble and—well," His smile was almost indulgent. "You're a doctor. Surely you can agree that keeping someone from being so self-destructive is a good cause?"
He glanced around the boring brown bedsit. He wanted to tear the walls down, smash everything into unrecognizable chunks of nothing. "Depends on the man."
He got a gun out of the deal. The familiar weight was soothing.
.
And so he meets Sherlock Holmes.
.
Sherlock sees people.
It's as if one of those long, pale hands slipped inside John's ribcage to cradle the dark, secret parts. Brought them to the light and didn't find them wanting, didn't shy away from the sharp edges.
John says "brilliant," and means it.
.
The man is back, checking up on him. John pictures the neat little hole he'd make in that smug forehead, the oily veneer sliding away to shock. He knows this man is the reason he has a therapist. They both know she'll do him no good.
"You're very loyal very quickly"
John doesn't want to think what he'd be without loyalty, without boundaries holding him in. The army isn't there to give him direction any more. He's not quite sure why Sherlock is the next thing to form the shape of him, why not a more upstanding man like Lestrade.
Perhaps because he thinks there might be understanding in those sharp eyes.
Or Sherlock will kill him and he won't have to worry about that any more.
.
"Good shot."
That really, really shouldn't be the hottest thing John has heard in ages. He tries to deflect, but knows Sherlock sees right through him. It's a nice feeling, having somebody who knows.
"Well, you have just killed a man."
He figured out long ago that something in him must be broken, to take a life like that and feel nothing.
"But he wasn't a very nice man."
He wonders how many corpses he'll pile up in the name of Sherlock Holmes, like grisly presents from a cat. Then they're laughing. Perhaps he's found somebody just as shattered as he is.
Interesting, to hear that the man with the umbrella is Mycroft Holmes. What kind of brother introduces a killer to his kin?
.
Sally, for all her bluster and insults, is a good person. She's honestly concerned for his welfare, warning him away from Sherlock.
It's hard not to smile. She thinks she's saving him.
.
Sarah is normal. John likes having her there; he can have dates and not see death everywhere. A measuring stick. But It's disappointing that she accepts the surface as the truth. He killed a man in front of her and she seems to have forgotten about it.
It's amazing, the things people make themselves not see.
John goes through the motions of dating but isn't particularly crushed that she hasn't initiated sex. He is too busy looking at the bruises fading on Sherlock's neck.
.
"I've disappointed you."
Sherlock doesn't understand.
John doesn't want Sherlock to be too much like him. John fights every moment to keep himself from slipping, claws out of numbness and into caring. If he doesn't make the effort to care about all those strangers that mean nothing to him, what would he become?
He isn't like Moriarty.
He wants to tear Moriarty's throat out with his teeth, feel the warm blood on his chin and the satisfying sensation of shredding flesh.
(In private, John never eats steak with knives or forks.)
.
When they finally meet, Jim Moriarty spends much of it laughing.
John will admit being kidnapped and strapped to a bomb is hilarious.
Sherlock's face when he sees John isn't.
As he grabs Moriarty around the throat, screaming at Sherlock, John wonders if the awful, clawing feeling in his chest is what he's been missing. It burns.
The only way to get out of this is to be very, very good at killing people.
Well then.
.
The police aren't happy, but let them go eventually. Sherlock has John's gun slid into the back of his trousers and it makes John ache. He wants to slide his hand in beside it and feel the skin-warmed metal. He's glad Sherlock thought quickly enough to ensure he didn't have to lose it.
They don't speak during the cab ride back to the flat, the air surrounding them like glass.
Sherlock breaks it into spider-webbed cracks as soon as the door to their flat closes. "John," tears out of his throat as he shoves the shorter man into the wall, like the space between them is too much to bear.
John slides his hands over that long neck. Watches grey eyes watching him. He could push his thumbs into the frantically pulsing veins, squeeze tighter and tighter. Sherlock would fight him—instinct is inescapable. He'd thrash, long fingers would claw at John's forearms, ineffectual. They'd stay locked there, until John's arms burned from the effort and Sherlock passed out. After that, it'd be easy.
His corpse would wear John's hand-prints until it rotted away.
They stare at each other, each playing out this next step, cocks already half-hard in their trousers.
Sherlock reaches up, slowly, until his hands mirror John's.
Mutually assured destruction.
John smiles. Sherlock quirks his lips and pushes forward until their lips meet. It's greedy, devouring, teeth and tongues. Their hands squeeze tighter.
Honest to God I'll break your heart
Tear you to pieces and rip you apart