“Promise me you’ll continue to record your observations if I can’t.”
“Not a chance.” John glanced toward the six-page spreadsheet Sherlock had affixed to the door of the refrigerator. Nope, still almost entirely incomprehensible. “I plan to be busy.”
“But John . . .” Sherlock wrapped two long arms around John’s waist from behind and buried his nose in John’s hair. “This is valuable data. The only way I’ll get a chance to examine behavioral changes during heat decoupled from pheromonal interference is if I take phanthoterazine again, and I’d really rather not do that. Not now that I’ll have you to spend my heats with.”
Like hell. “Damn well better not,” John growled, and spun in Sherlock’s arms to shut him up with a thoroughly dirty kiss. “No drugs. Well, other than our birth control.”
“An impartial observer next time, then.” Sherlock arched one eyebrow. “Would have to be a woman - Molly might, if I complimented her enough first. Or Mrs. Hudson - she’d be happy to watch you fuck me through the mattress. She’s been hoping for ever so long-”
“Shut up.” John felt a delicious wave of possessiveness wash through him, and for once he didn’t have to fight it. My omega. MINE. “I’m not sharing you - ever. Not even for an experiment.”
“Guess you’ll just have to be observant, then,” Sherlock said with feigned reluctance, “and I can interview you about it later. Because I estimate we only have an hour or two left before I’ll be thoroughly mindless and begging for your cock in my arse.”
John licked the sensitive spot just over Sherlock’s carotid which he’d only yesterday discovered set the consulting detective to shivering. “Best get recording while you can then, hmmm?” he murmured in Sherlock’s ear. “Don’t mind me - I’ll just be warming up.” He punctuated his words with a gentle bite to Sherlock’s earlobe, earning himself a shaky moan in exchange. “Got to be in top form before the main event, after all. And I’ve been practicing so hard these last few days.”
Seeing Sherlock out of his mind with lust - and being clear-headed enough himself to notice - was a novel experience for John. They’d spent two and a half hours in a sort of heat-induced limbo, with Sherlock determinedly measuring his own blood pressure and respiration and heart rate every five minutes while John did his level best to invalidate the data by making Sherlock’s heart beat as fast as possible. So far, his favorite method of taking Sherlock’s pulse was definitely by mouth, licking and sucking at the skin over various major arteries until Sherlock swore and entirely lost the ability to keep count in twenty-second increments. Eventually Sherlock sat up and stripped the rest of the way, his eyes dark, and dragged John to bed. They left Sherlock’s spreadsheet on the kitchen table.
“Yes,” Sherlock murmured. “Need you now, John. I’m literally going to die if you don’t get your cock inside me right this very minute.” He flopped over on his stomach and ground his bare arse back against John’s hip, the only part of John he could easily reach. “Get undressed and fuck me.”
“Thought you wanted data?”
“Want your knot,” Sherlock groaned. “Please - you’re not this cruel. I need you.”
“Yeah, okay.” John undid his belt and trousers - which he’d very deliberately been keeping on as long as possible - and dropped them both to the floor. It meant a lot for Sherlock to let him see this, he knew. It had been amazing enough that Sherlock had let his defenses down over the last few days and allowed John to see him naked and needy in the throes of orgasm. It was light years beyond that to know that Sherlock trusted him enough to see him through his heat like this, when they both knew Sherlock would be reduced to his basest, animalistic state and John would still be relatively clear-headed. Sherlock was entrusting John with the care of his transport and his mind both, and the significance of that still left John a bit dizzy.
“I’m so empty,” Sherlock whined. “John . . .”
“God, you make a gorgeous picture.” John laid one flat palm on Sherlock’s writhing arse and took a moment to just look. Pale skin, dark curls already tousled into fuck-me readiness, Sherlock’s entire body twisting in long, graceful arcs against the mattress. Begging. And John was the only alpha to ever see him like this. God fucking damn.
The relief when he finally eased himself into Sherlock’s drenched hole was nothing short of a religious experience. Sherlock howled, buried his face in his pillow, and came in an explosive burst of limbs which left him sprawled flat on his stomach. His orgasm would have knocked John out of him if John hadn’t had the foresight to wrap an arm around Sherlock’s too-thin ribcage and hang on tight. He waited just long enough for Sherlock to recover, then started a pattern of thrust-and-nudge strokes which kept Sherlock completely unable to catch his breath and brought John to the edge of orgasm in less than a minute. He pressed close against Sherlock’s back as he moved, nuzzling the nape of Sherlock’s neck and breathing deep at where the pheromones would have been the strongest if this had been a normal heat.
“Going to bite you,” John murmured directly into Sherlock’s ear. “The next time you come, I’m going to fill you with my seed and I’m going to knot you and I’m going to bite down right here-” - he nuzzled at Sherlock’s scent gland - “- and we’re going to bond. And you’ll have me for ever and ever, just as I’ll have you. That sound good?”
“Yes,” Sherlock groaned. “Make me yours, John - please.” He wriggled backwards, skewering himself further on John’s cock and forcing John’s growing knot tighter up against his hole. “Just - knot me, now!”
He didn’t have to ask twice - the edge of desperation in his voice was enough to have John already pushing harder, forcing Sherlock’s body to take just that little bit more. The moment everything gave and John popped fully into Sherlock’s slick arse, they both let out matched cries of relief.
“Bloody buggering hell.” John slid a hand down over Sherlock’s cock, even though they both knew it was unnecessary - Sherlock was already keening, his muscles locking up in preparation for another orgasm and then his first relief of the heat. John felt it, too, the tightening in his groin, the little hesitation before-
Fuck. It didn’t take thought, just instinct - Sherlock arched his back when he came, baring that beautiful pale column of neck, and John covered the entire scent gland with his mouth before biting down hard enough to break the skin. They both jolted and then John was coming too, his knot swelling the rest of the way and locking their bodies together even as the unique chemicals that made up Sherlock filled his mouth and rolled through the rest of his body. They tasted the way Sherlock’s pheromones smelled - nothing definable, nothing John could compare anything to, but reminiscent of all the times Sherlock would flounce around the flat or end up pressed against John in the cab after a long chase or just when he’d fall asleep on the sofa with his legs stuck up in awkward angles and John could study him at his leisure. He smelled and tasted like home and John’s entire body tingled as the bonding swept through and took hold. Below him, Sherlock was moaning and shivering in tandem.
“God, that was . . .” Sherlock trailed off as another long shiver overtook him. “I can feel you in me, John. I can actually feel you inside me.”
“I should bloody well hope so,” John deadpanned, and nudged his knot a bit more firmly into Sherlock’s arse. The movement provoked an entirely satisfactory groan.
“Not - not that,” Sherlock grumbled. “I mean I feel you. The bond. The chemicals in your saliva, chasing their way to my posterior pituitary gland and altering my own internal chemistry to be more like yours. I want - I need you to kiss me, John.”
That was something John could do. The angle was awkward, still locked together as they were by John’s knot, but John managed to get his lips on Sherlock’s and whole volumes of information were shared through their kiss. All John’s promises to protect and cherish his omega, to be the best bondmate he could be, to be Sherlock’s helpmate and partner and lover and keeper and friend, all were returned in kind by Sherlock’s ardent desire to reciprocate. To welcome John as alpha and partner instead of owner or lackey. To love John as best he could.
They snogged until John’s knot finally softened. Even then, they exchanged tiny, wordless kisses while John got them both cleaned up a bit and brought Sherlock a cup of water and a piece of toast with his favorite raspberry jam.
Had to keep up their strength, after all.