They're at dinner when Sherlock's fingertips brush the back of his hand. It's an innocent touch, meant to divert his attention away from his lo mein and back at Sherlock where it belongs, but the way his body reacts is anything but chaste. John jerks his hand away like he's been burned, and flushes when Sherlock's eyes narrow.
"Startled me," John explains. It's a weak excuse, and he knows it, but it's the only thing he can think of to say.
"I didn't realize lo mein was so engrossing," Sherlock replies. "Interesting."
John spends the next two weeks trying to convince himself that the incident at the restaurant was just a fluke. It almost works, until Sherlock comes along and fucks it up.
They're standing in the living room together, John with a startled expression on his face and Sherlock with his hands pressed to either side of John's head. Sherlock is telling him to, "think, John, think, try to remember where you put the boric acid when you were cleaning," and John is trying to figure out why everything has to be so goddamn dramatic between them, when Sherlock's hand shifts and one of his fingers grazes the top of John's ear.
"Under the sink," John gasps and takes a step backwards, out of Sherlock's grasp. His heart is racing and his skin is tingling, and he has to fight to keep his voice steady. "I put it under the kitchen sink."
John can feel Sherlock watching him as he turns to leave the room.
Touching Sherlock feels dangerous, but John keeps doing it anyway. They've always had a tactile relationship, so an abrupt change would be sure to arouse Sherlock's suspicions. Besides, John wants to prove to himself that he can deal with this attraction without going completely mad.
It's fine until Sherlock's feet end up in his lap.
They've taken to sitting on the couch together in the evening. It's easier for John to see the television, and Sherlock is a creature of habit. For the most part, it works out; John lounges at one end with a beer and the remote, and Sherlock curls up at the other end with his laptop and a book. John really believes he's safe until the night Sherlock stretches out lengthwise on the couch and plants both feet in his lap.
"I'm not giving you a foot rub." John tries to sound vaguely irritated instead of uncomfortably surprised.
"I don't need one," Sherlock replies without looking up from his book.
John glares down at Sherlock's feet, then swallows and looks back at the television. Feet have never done anything for him, but the fact that they're Sherlock's and they're touching him is all that seems to matter. John tries to stamp down the arousal simmering in his veins.
Things get worse when Sherlock moves and one of his feet comes this close to brushing against John's cock.
"I'm going to bed," John announces. Sherlock's feet tumble out of his lap as he stands.
Sherlock lowers the book to peer up at him. "It's half eight."
John can feel his cheeks burning. "Long day at the clinic."
Sherlock gives John a head-to-toe look that makes John's knees go weak, then turns back to his book without a word.
"Good night," John mutters, and once again flees for the sanctuary of his bedroom.
John has never noticed anyone's hipbones before, but it's hard not to notice Sherlock's when he's draped over the settee with his dressing gown parted in the middle and his pyjama bottoms slipping down so far it's almost indecent. John can't stop wondering what they'd feel like under his palms, and whether Sherlock would gasp if he licked them.
"Seventeen minutes," Sherlock murmurs.
John jerks to attention. "Sorry, what?"
"That's how long you've been staring at me: seventeen minutes," Sherlock drawls, then rolls his head to the side and opens his eyes. They're clear and bright, and they burn straight through John, right down to the guilty core of him. There's a long pause before one of Sherlock's hands slides down to his hip, and he rubs his thumb over his hipbone.
John's cheeks burn.
"It'll be dangerous," Sherlock warns him. The wariness in his expression is heartbreaking.
John slips out of his chair and crawls over to the sofa to press a chaste kiss to the back of Sherlock's wrist. When he glances up and Sherlock nods at him, he closes his eyes and grazes Sherlock's hipbone with his lips.