Disclaimer: Sherlock isn't mine.
AN: Second part as promised. Unsure when third part will be up, but hopefully some time soon...
"You kissed me," says John the next morning, absently, as he hunts for something edible for breakfast. He briefly wonders what it says about his life that a half-remembered sensation of his flatmate kissing his forehead doesn't really seem that unusual next serial killers and eyeballs in the microwave.
He opens the fridge, sees the tupperware boxes full of entrails, and shuts it again almost instantly, stomach turning ever so slightly. "Oh god, Sherlock, really-"
"No I didn't." Sherlock is perched on the edge of a rickety wooden chair in the kitchen – because the verb 'sit' just doesn't seem to cover the way he balances on the very edge of the chair, legs tucked under it and feet hooked around the legs at the back – sipping hot, sweet black coffee from a chipped navy mug. He blinks serenely at John's disgusted expression and cradles the mug in his hands, steam rising from it and swirling as he inhales.
John decides not to press the point with the entrails too much, as he knows from long experience that arguing just seems to encourage Sherlock. "Look, if you're going to- to keep revolting stuff in there, at least put a note on the door or something, okay?" Sherlock nods, not looking like he's even paying attention, and takes another sip of coffee.
"And yes you did," John continues, pulling open the bread bin and blinking in surprise when he actually finds bread in there. He pulls it out, examines it, and waves it in Sherlock's direction. Sherlock nods, which he takes to mean it's safe to eat, so he slips two pieces in the toaster and twists the dial. Then he checks the kettle – boiled bromine does not smell nice – and flick the switch on that too. The kitchen fills with the noise of electrical whirring and the noise of water slowly bubbling.
"No I didn't." Sherlock takes another sip of coffee, face still impassive.
Trying to hold a conversation with Sherlock, John reflects, is like trying to argue with a highly intelligent five year old with a complete disregard for logic or reality when it suits them. He rubs a hand over his face, sighs, and leans back against the counter. "Yes, you did, Sherlock, I remember it. You kissed my forehead in the middle of the night when some god-awful screeching noise woke me up."
"Oh."
John is silent for a minute or so, stunned by the intelligence and eloquence of Sherlock's response. The toast popping up with a metallic ding overrides his internal groans of despair, and he hunts around for a plate, fails to find one, and instead places his toast on the small plastic chopping board. It's sort of plate-like, he reasons, spreading butter with a carving knife because the butter knives were all melted down by Sherlock last week when he wanted to find out if acid or fire was more effective at destroying metal. "And that's all you've got to say about that?" he says, finally. "'Oh'?"
Sherlock makes a non-committal noise in the back of his throat, and John looks around. He finds that, to his surprise, the consulting detective's eyes are fixed on the floor. Usually they follow him around the room like a lost puppy when he prepares food. Sherlock takes another sip of coffee, realises there's nothing left, and sets the mug down on the table.
"What's that supposed to mean?" John turns back to his toast, and begins the long and dangerous quest for something to put on his toast. He finds an empty jar of marmite, a jam jar filled with what looks like blood, another jam jar missing a lid that has a dead wasp lying in the bottom and a bottle of honey that has half crystallised, which he sets to one side as a stand-by unless he can find something better. "It's a bit… out of character for you, isn't it? The whole human contact thing. You don't even like shaking hands."
There is silence. Sherlock picks up his mug, raises it to his lips, remembers there's nothing left, and sets it down again. "I…" He takes a slow breath, as if he's trying to taste the air. "You waited up for me," he says eventually. Even though it doesn't exactly answer the question, it sort of does, and John inhales quietly in surprise when Sherlock follows his words with, "Thank you. That was… kind of you. I appreciate it."
John contemplates this in silence for a moment, opening more cupboards in his valiant quest to find some jam, or at least some marmalade, and Sherlock apparently takes this as meaning he's done something wrong. "Isn't that what people do, anyway?" he adds, and there is a vaguely, curiously hopeful tone in his voice that is there when he asks John to confirm that he's behaving like a normal human being. "Kiss people on their forehead when they're saying goodnight?"
The sound of shifting boxes and pots and jars fills the kitchen for a moment as John contemplates again, this time wondering how to explain the nuances of intention such an act carries – how a parent kissing their child on the forehead is different to a wife or husband doing the same with their spouse, and how a possibly-asexual and probably-autistic consulting detective kissing his flatmate's forehead in the middle of a darkened lounge doesn't really fit into either.
He gives up after a moment, and simply says, "No, no, you're right. Just a bit odd, coming from you." He finally finds a jar labelled in fancy font that proclaims itself to be marmalade, pulls it off the shelf with a small cry of triumph, opens the top, and-
"What the- urgh, that's just- Sherlock, one of yours?" John holds out the marmalade jar as far away from his nose as he can, face turned the other way and twisted into a vaguely revolted expression. Sherlock slips off his chair, pads around the table and takes the proffered jar, face lighting up into a look of delight most people usually reserve for kittens or puppies when he sees the thick coat of green and white mould covering the remaining marmalade and slowly but determinedly climbing the sides of the jar.
"Tolypocladium inflatum, fascinating," he mutters softly, and then see's John's disapproving and slightly nauseated face. "No, no, it's not one of mine. Rather nice, though, even so." He snatches up the lid from by the chopping board, screws it on, and the jar is added to the ever-growing clutter on the kitchen table.
John sighs, gives up, and dollops chunks of crystallised honey on his now-cold toast. Walking over to the table and setting the chopping board down on a miraculous piece of space that has only been covered by newspapers and a page of cramped, borderline-illegible notes in Sherlock's looping handwriting, he moves to pull a chair over, and is stopped by a hand resting on his shoulder.
"You're upset with me. I've done something wrong," Sherlock says softly, and it's the lack of any readable emotion in his flatmate's voice that tells John how anxious he is.
"No, Sherlock, you haven't, it's just…" John runs a frustrated hand through his hair and turns around, looking up at Sherlock's blank face. "Kissing is complicated, okay?"
"What do you mean?" Sherlock frowns. "Is it the same as that 'date' thing?" John had never managed to explain to Sherlock's satisfaction how going to the cinema with a girl was different from going to the pub with some mates, mainly because of his reluctance to start a discussion about sex with someone who seemed to be entirely disinterested and confused by the whole notion.
"Sort of. Look, kissing – it's something you only do with people you really like, yeah?"
"I didn't kiss you on the lips." Sherlock's frown deepens, and John feels an odd sense of relief that Sherlock at least knows what kissing people on the lips implies. "It was only on your forehead. You looked disturbed, I thought it might comfort you." He pauses. "It seemed to work."
And that, that right there is the problem, thinks John, closing his eyes for a second in an attempt to find a reasonable explanation. It worked.
Eventually, he says, "Kissing someone's fore- kissing someone's anywhere, really, other than maybe their cheek sometimes, sort of indicates that you'd like to kiss them on the lips at some point in the future. It-"
He's cut off abruptly when Sherlock's fingers close around his wrist, tugging him slightly closer, and then one hand's tentatively touching his cheek, and lips are pressed against his forehead. They're dry and slightly chapped and surprisingly warm – John's not sure why that's surprising, but Sherlock always looks like such a cold person, all pale skin and icy eyes and dark clothes and sharp angles.
They stay there like that for a second, connected hand to wrist, cheek to hand, lips to forehead, and then Sherlock takes a step back, his experiment complete. John watches him, waits for the detective's eyes to widen in understanding, in comprehension, with the light of some sudden deduction.
They don't. The bewilderment grows on his face, brows furrowing further, and then he lets go of John's wrist and is suddenly gone; the door swings shut behind him, his coat is missing from the rack, and that is that.
John stands there a minute more, blinking at the empty kitchen and breathing slowly. Then he sits down and eats his cold, sickeningly sweet toast thoughtfully, mouth chewing on the dry bread and sickly chunks of sugar crystals in an automatic motion. His gaze is fixed somewhere on the cupboard opposite, hovering unseeingly on a small burn mark in the corner.
Long after his toast has been reduced to crumbs and stickiness and the water in the boiled kettle has cooled again, he sits at the table, head in his hands, the tops of his fingers and the blunt edges of his fingernails resting lightly against the place where Sherlock's lips had touched.