Work Text:
"I'll sleep fine tonight."
"Quite right."
John had felt a subtle excitement in response to Sherlock's statement, even if he'd brushed it aside, tried to think nothing of the smile on Sherlock's face as he said it. After all, Sherlock had made it quite clear that romantic entanglements were off the menu - as were food and sleep, apparently. And as much as John was decent at reading other people's body language - he had to be, being a doctor - he didn't have Sherlock's near-supernatural talent for it.
After a delicious meal in a tiny Chinese restaurant - John was still processing Sherlock's explanation of how you could find the best authentic food by reviews averaging 3.5 stars - they had started the walk back home with companionable chatter up until the point when Sherlock took his hand.
The odd thing was, John had continued walking for a few seconds before realising exactly what he was doing.
"Sherlock?"
"Mm?"
"What are you up to?"
Sherlock looked down at their linked hands, and frowned when John pulled his free. "I'd... thought that much would be obvious?"
John was very quickly learning that Sherlock's idea of 'obvious' wasn't quite the same as everyone else's. "What happened to 'everything else is transport'?"
"I'm between cases," Sherlock said, as if that explained everything.
John shook his head, not sure whether he wanted to laugh or grimace, and carried on walking. The damned thing was, his hand felt empty now, itching for contact.
When Sherlock didn't try to take his hand again John decided to write the incident off as part of Sherlock's inability to behave like a normal human being. He brushed his teeth and settled into bed, watching shadows pass by in the hall as Lestrade's crew continued their work processing evidence from the crime scene. It was strange to feel so tired but so alert all at once, his mind racing even though his body was exhausted now that the adrenaline rush of running and shooting had worn off, and it was a relief when the door opened and Sherlock appeared in silhouette.
"Sherlock closed the door behind him, leaning forwards slightly. "About earlier. I may have been - rash."
John nodded slowly, biting his tongue; men like Sherlock did not apologise easily, if at all, and interrupting his attempt at one now would likely cut it off altogether.
"I consider myself married to my job, but I'm open to having an affair."
John snorted, grinning despite himself. "You want me to be your bit on the side."
"Correct," Sherlock replied.
Damn that Mike, throwing him in at the deep end with this gorgeous and very, very weird man. He should have remembered John's type from too many nights of too many beers at the end of each semester, and the bad choices John made as a result of them. "Ask me again in the morning."
"When you've had enough time to talk yourself out of it?" Sherlock's eyes might have been cast in shadow, but the challenge in them was crystal clear.
John couldn't resist getting up to kiss him. He hated backing down from a challenge, too.
For someone who seemed to consider his body an inconvenient means of moving his brain from place to place, Sherlock was rather enthusiastic about putting it to good use when the opportunity arose. John wasn't entirely unfamiliar with anonymous or near-anonymous flings, but he'd never before experienced the oddity of someone picking up on his every tick, every like and dislike, quickly enough that it felt as if they had been together for months by the time they were both naked under the duvet.
It didn't hurt that there was a thrill of being caught mid-act, Sherlock stilling every time the susurrant voices outside turned silent, and John's concern quickly became less about getting caught with Sherlock's lips on his cock and more concerned that Sherlock might just stop altogether before he'd had a chance to finish.
His own breath hitched as he drew close to coming and he fisted one hand in the pillow, the other in Sherlock's hair, trying not to laugh at a muttered "Ow" as Sherlock pulled back, unimpressed with the hair-pulling.
John let go, and Sherlock shifted up the bed until his face was inches away from John's, but still not close enough to kiss.
"What -"
"Shh," Sherlock whispered, glancing over his shoulder at the door for a moment before turning back to John and taking his cock in hand, moving torturously slowly. "I need to see."
Oh, he was going to regret this someday. He just hoped that regret came later rather than sooner.
John took hold of Sherlock's erection and matched him stroke for stroke, fought the urge to squeeze his eyes shut at the last minute, determined that if Sherlock wanted to see everything, he would; and for all that it was Sherlock's mouth that had brought him to the edge of coming, and Sherlock's hand that finished him off, it was those eyes, devouring him, that made it necessary to bite his own lip hard enough it hurt to avoid yelling.
Sherlock took a less painful option by leaning over to bury his face in the pillow when he came, which as far as John was concerned was cheating, and an imbalance he'd have to rectify later.
Sherlock rolled onto his side, pulling the duvet up to cover John's shoulders, and stared at John for a moment, looking puzzled.
"What?" John asked, disconcerted by the staring.
"You're thinking about next time," Sherlock said, sounding almost young in his disbelief. "I've never had a 'next time' before."
"Glad to have surprised you," John said, watching Sherlock climb out of bed and start dressing his narrow frame. John decided he would have to take advantage of any break between cases to make sure someone was feeding this strange, beautiful weirdo who'd torn through John's world like a natural disaster.
"It wasn't surprising at all, actually."
John grinned. He didn't need to argue, but couldn't resist. "Liar."
Sherlock finished tidying himself up, walked over to the door and opened it out onto the corridor, light illuminating the small, almost secret smirk on his face. "I know."