John doesn't hug. He's friendly, of course, even demonstrative. Always happy to shake hands or link arms or clap a hand on a shoulder, but hugging…he skitters away. Won't let it happen, unless it's grappling for a hold, like with Moriarty in the pool. He can't seem to bear it. Sherlock wants to know why.

That's not the only thing Sherlock wants to know about John Watson. The list he keeps in his head comprises three hundred and seven items at the moment, starting with why exactly John stays with him and continuing on to the names and identifying details of the three men with whom John had long-term sexual relationships before Sherlock.

Somewhere in the first third of that list — the items aren't in strict order, they shift up and down based on a complicated set of factors including but not limited to the weather, John's outfit, and the severity of his psychosomatic limp that day — is the question about hugging. It's surrounded by questions about John's family, about his father's death, because John's blase answer of "cancer" is a lie, and Sherlock has as yet been unable to find anyone who will say anything different.

However, John tends to react badly to questions about his family, his father, his childhood, and so Sherlock continues his investigations without consulting John. School records show that John was extremely quiet when he began school, and just enough older than the other children that he really should have enrolled the previous year. He was far behind, in terms of social development, and there was some question over his mental faculties.

This confuses Sherlock for a moment. John is no genius, certainly, but deficient? Not possible. He considers the man John is now: quiet, yes, but not silent, and never passive in the face of challenge. When they tested John, luckily, he proved to be quite clever, just shy and uninterested in talking. John was allowed to continue school, to stay in his class despite being nearly a year too old for it. His progress reports ooze concern: John is very quiet. John doesn't seem to have many friends. John doesn't play with the other children. John hates to be touched.

The man John is now likes touch, as long as it's not a hug or any sort of confining hold—ah. Stupid, should have seen it earlier. Quiet, too old, shy, unfriendly, a distaste for being trapped in someone's arms: abuse. Mostly physical, almost certainly with some verbal and/or emotional components, but absolutely abuse. Sherlock digs back through the reports, looking for evidence. He finds enough, plenty, so much that he fires off strongly worded emails to the GPs who set John's broken bones and the teachers who thought John "slow" while missing every other obvious sign of persistent abuse. Those idiots, absolute bloody morons. It was all right there, in print and photos and common sense; Sherlock doesn't even have to think hard to see it.

John comes to school with a deep and poorly-sutured (obviously done by someone with rudimentary training, but not a doctor, nurse, veterinarian, or other medical professional) laceration on his left calf, because a dog bit him. Impossible; the cut is the wrong shape and size, clearly made by a slightly dull blade wielded by a right-handed adult, and besides that John is amazingly good with dogs. All animals love him immediately and unquestioningly, what a stupid lie.

John comes to school with two fractured ribs from a car accident with his parents. There are no corresponding accidents in the newspapers, and besides John's sister, who would have been in the car as well, is unharmed and never mentions the wreck to anyone, and no insurance claims are ever filed. An even stupider, even more obviously false fabrication — was everyone at John's school incapable of rational thought? Sherlock makes a note to run background checks; perhaps John's father had leverage of which Sherlock is unaware. There must be a reason.

John comes to school with a broken wrist he allegedly got falling off of a bicycle; unlikely again, he's anything but clumsy and the force required to break a wrist in that manner is difficult to achieve from a simple fall. A man's hands, though, twisting and crushing, those could cause that damage. The GP should have seen that. Sherlock can see it, at one in the morning without medical training and without a tiny, silent, fragile child begging for help the best way he knows how.

Sherlock has never yet killed someone with his bare hands. A few seconds pass as he tries to decide who he most wants to murder at the moment: the man who abused John (Sherlock is willing to find a way to reanimate long-dead flesh if it means he can kill John's father himself), the doctor that didn't see it, the teachers that made John learn to hide it, the world that ignored it all. There are many viable candidates, but Sherlock sets them aside for further consideration at a later date. It is then that Sherlock is suddenly aware of John's presence behind him. He doesn't turn, because he's not certain what his face looks like at the moment and is even less certain of how John will react.

"That's my laptop, you know." A sigh, and the sound of John settling into the sofa. "Why are you poking through my life, Sherlock?"

Sufficiently calmed, at least on the surface, Sherlock swivels in his chair. John looks tired, shadows under his eyes — it was a rough day at the surgery, and Sherlock knows he should probably wait to have this conversation later, but the words bubble up out of his mouth. "Your father beat you. Why?"

"What?" John is a better actor than Sherlock had thought, but the minuscule twitch and involuntary way his eyes scan the room tell the truth. "No, he didn't, what are you talking about?"

"Don't presume to lie to me, John." Sherlock steeples his fingers, presses them to his lips, takes a deep breath. "Your father broke your wrist, twisted it; your father broke your ribs. Your father sliced you with a dull knife and didn't take you to a proper doctor to get it stitched. Explain this to me, John. I'm no good with motives."

"Wh—no, Sherlock, I had a rash of bad luck as a kid, all right?" John's not even looking at him now.

"Liar." This strange anger is unsettling; Sherlock finds himself wanting to strangle John's father, wanting to punch a wall, wanting to kiss John until he stops lying. Many different impulses, none of which would be helpful in this situation. Sherlock stands, slips onto the sofa. Turns so that he is facing John, who is looking anywhere but back at him. "He died ten years ago, of cancer. You left home the next day. Harry was already gone, your mother long dead from—" stupid, stupid, sometimes he loathes himself more than usual. "Ah. He blamed you."

"I didn't do anything," and John is on his feet, face blank in a way that to normal people wouldn't mean anything but to Sherlock is abjectly terrifying. It's the blankness John wore in the hospital after Moriarty, when he didn't speak for a week and Sherlock nearly went mad from fear. "I didn't do anything, and Da never touched me, just back off."

The front door slams and Sherlock cannot move. Stays seated on the couch for the night. Does not return to his investigation, does not answer Mrs. Hudson's emails asking about domestics, does not track John to his favorite pub and demand answers. He does none of the things he wants to do, because all that would result from his action would be more pain for John.

—-

John is drunk. This is John has a pint on match nights, or a shot with friends at a party, but never gets drunk. He's been around his family and Harry and stitched up enough wounds from bar fights and pronounced enough people dead in stupid accidents to know better.

And so when he realizes, strangely detached, that he is in fact absolutely wasted, it's somehow the funniest thing he's ever experienced. He nearly howls with laughter, stumbling over nothing and falling flat on his face; lies on the pub's dirty floor, still laughing, and doesn't resist in the slightest when strong hands pick him up.

"Hullo, Greg, you piece of utter shit!" John can hear the slurring, can feel the thickness of his tongue. The tiny rational bit of his brain not already drowned in booze thinks that this is an incredibly embarrassing situation. The rest of his brain is occupied with working desperately not to piss himself or lunge at Lestrade — whether to punch or kiss, he'd find out later.

"You've had quite enough, John," and Lestrade is angry, seething with it, and John decides to punch him instead of kiss him because if he wanted to kiss a man who hated him he'd go kiss Sherlock, wouldn't he?

Luckily for Lestrade, John's depth perception is shot to shit. His mouth still works, though, and Lestrade grits his teeth as he drives John home. Invectives and obscenities and insinuations volley up at him from the floor of the backseat, where John slid during the struggle. "And as for your mum, Greg—"

"Shut up, John, all right?" Lestrade is livid at Sherlock for letting John go out and get into this state. "I've no idea what happened with you two, but you need to kiss and make up, or whatever it is you do when you're dating a sociopath."

"Fuck you, Greg, and fuck him too." John's grumbling now, not yelling, which is a vast improvement for Lestrade's ears and mental state. All of that improvement, however, goes to waste when he pulls John's boneless form out of the car and up the stairs. John passes out, or passed out in the car; either way, he's dead weight and none too light, and Lestrade fuckinghates carrying drunks.

"No need to help with the door, Sherlock, that's fine," it's not like he hasn't had to break in a few times before. It's two in the morning, and Sherlock is sitting stock still in a chair at a desk, staring at the laptop Lestrade knows is John's. "Could use a bit of your muscle here, though, to get him upstairs."

The detective doesn't respond. Doesn't change his breathing pattern or his posture, doesn't look around, doesn't make a sound. Lestrade huffs and puffs his way up the narrow staircase. As a friend, he knows he should help John out of his clothes and all that, but he's still stinging from the paragraphs of yelling, particularly the digs about his wife, and so he simply plops John down on the neatly-made bed and leaves him there.

As Lestrade leaves the flat, he hears Sherlock stand: the clicking of the chair's wheels, the creak of the floorboards. He thanks his lucky stars that Sherlock's the one who'll have to deal with John's guilty hangover in the morning, not him, and he goes home.

—-

John opens his eyes unwillingly. There is absolutely nothing he would rather do than go back to sleep, preferably for the rest of his life. Sherlock's face is next to the bed — he must be crouching, that can't be comfortable, and John has to stop himself from scooting over and making room on the bed.

Sherlock's face is wan and still, and his mouth is moving, and John forces his sluggish brain to listen. It's a never ending stream, nonsense syllables, but it starts to sort itself out into, "I'm sorry, I'm sorry, I'm sorry." Just over and over, like Sherlock can't stop himself, like he's a record needle that's stuck. "I'm sorry, I'm sorry, I'm sorry."

"Sh-" a pause, and John gauges whether he's going to throw up or not. Not, he decides, and continues, "Sherlock, stop, shut up. What are you sorry about?"

The detective is still murmuring the phrase, again and again and again, and John hates everything in the world because he's hungover and upset and—oh, actually he is going to throw up.

A leap from the bed and a scurry into the bathroom, apparently, is what it took to break Sherlock's reverie. "John?" He stands, joints popping and snapping as he unfolds himself, and strides into John's restroom.

The doctor is moaning, his face in the bowl of the toilet, good arm braced to hold his torso up. "Jesus. Bloody. Buggering. Shit." The way the porcelain reflects and reshapes the sound of John's voice is fascinating, distracting, and Sherlock makes a note to experiment with it later.

"I'm so—"

John holds up his free hand. "Sherlock." Lifts his head out of the toilet bowl, peers blearily at Sherlock. "Shut it. No, shh, no. I don't want to hear—" a pause, a concerned look on his face. "No, okay, good. Might be done with that." He refocuses on Sherlock. "I…I may have overreacted just a bit. You shouldn't prod into my life like that, all right, but I shouldn't yell and storm off and drink—" Just in the nick of time, John lowers his head back into the toilet.

Sherlock is paralyzed, uncertain. Social cues are ridiculous, and he's only vaguely aware of most of them anyway. He runs through every depiction of this type of situation he's ever read or seen: most of them assume pregnancy on the part of the vomiting party, but the concept is basically the same here. He hesitantly, ever so lightly, places a hand on the curve of John's back. Rubs soft concentric circles.

Apparently that was the right thing to do, because John's heaving and retching slow and cease. He flushes the toilet, scrubs his face, rinses out his mouth — Sherlock stays on the floor, unsure of the proper reaction. They never show this part in films, after all.

—-

John is sitting on his favorite chair, leaned back, holding a cup of tea with both hands wrapped around it like he's drowning and it's a life preserver.

Sherlock is perched on the edge of the couch, hands clasped in front of him as if to stop them reaching for anything else.

John's tea is cold. Sherlock's hands are tingling from reduced blood flow.

"My da wasn't bad when he was sober."

It's the first time they've spoken in hours, since the vomiting. Sherlock is weary, stiff and sore from stillness. "Oh?" Useless word, stupid, but he's swimming up out of the depths of his own mind, he can be a little inane for a moment.

"He took it hard, my mum's death. Never really got over it, I guess, and with me there—" John's hand twitches, nearly spilling the cold tea. He sets it down, almost as an afterthought. Not a sip is missing.

"You reminded him of her."

"We look a bit alike, I suppose, more than Harry anyway." John's hand twitches again. "At least, that's what I told myself, thinking that's why it was me and never her."

Sherlock is silent. Watching. John's physical communication is second to none: a quirk of an eyebrow or a set of his mouth can speak volumes to anyone observing. This slack face, telling nothing: Sherlock hates it. "Stop making that face." Wrong thing to say.

"What face?" And there's John, eyes alive and a bit angry instead of cold and empty.

Sherlock could cry, if he was that sort of man. "Never mind."

John looks a bit better as he tells the rest. The first time his father hit him, it was an accident: the man was drunk and angry and three-year-old John had gotten in his way, blundered into his fist. And it never really stopped, not until John was fifteen and left home. Moved in with a rugby mate from school, slept on his sofa for three years.

"Your father never came after you?"

"Simon — that was my mate — he was a big guy, with a big father and two big brothers. They kept him away, I guess. He was small, you know, not to me, but to you he'd have been small." A dry chuckle that Sherlock hates. "Seems funny, thinking about it. We'd be pretty close to the same size now. He always seemed huge, but he wasn't, and now he's dust and bones and I'm solving mysteries."

Sherlock's hand reaches out. He touches John's knee, lightly, as if to test that he's real. "You're remarkably well-adjusted, you know."

A real chuckle, this time, with John's edge of brightness around it. "That means…a surprising amount, coming from you." He places one hand atop Sherlock's, and they sit like that for some time.

—-

There are, at present, three hundred and seven things Sherlock wants to know about John Watson. Forty-eight of those items now reside in a new section of the list dedicated to things Sherlock wants to know but will never ask about. Some things are not worth knowing, he has decided, if the finding out hurts John. Why exactly John stays with him is still at the top, and will always be, no matter how many similar-but-unique answers John gives him.