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He should have known he'd come down with the flu. Three different doctors at the surgery had already got it, which was why he'd had so much work lately—he supposed it had only been only a matter of time before he ended up ill as well. Still, he hadn't really been prepared; his immune system was normally up to the task of keeping him healthy.
He called in to the surgery (Sarah laughed at him—a locum doctor having to cancel due to illness!—which John thought was a bit unsporting) and then stumbled down the stairs to make tea. Sherlock was doing something at the table but John knew better than to ask him for help. He walked around him, filled the kettle and turned it on.
"You didn't take your suppressants," Sherlock said. His voice sounded odd.
John turned. Sherlock's hands were steady where they lay on the microscope, but he was staring at John, frowning in concentration. "Suppressants?" John said.
"For your heats."
"Sorry, my what?"
"Your heats," Sherlock said. John blinked at him. "Or your cycles. Whatever your community calls them."
Christ, it was too early for this particular brand of nuttiness. "My community? You mean doctors?"
"No, your community," Sherlock said with peculiar emphasis.
John shook his head and leaned back against the counter. "I don't know what you're talking about. If you're not doing anything, could you run downstairs and ask Mrs Hudson very nicely to make me some chicken soup?"
"You must have stopped taking them recently." Luckily John was used to being completely ignored. "You haven't had a single heat since you've been here and there's been time for two or three. Why did you stop?"
"Two or three what?"
"Heats!" Sherlock yelled. "When did you stop taking the pills?"
"What pills?"
"Whatever pills you've been taking." Sherlock looked halfway irritated, halfway off balance.
"I haven't been taking any pills," John said.
"Yes, obviously. When did you stop?"
John rubbed one finger along his forehead. "I have not been taking any pills since I moved in," he said. "Paracetamol. Sometimes. When something you got us into has turned me black and blue again. That's it."
There was a sort of dawning horror on Sherlock's face. "Your parents. Were they human?"
"What kind of a bloody question is that, especially for someone with a fever?" John yelled. "Oh, by the way, in case your deducing mind couldn't tell from the pyjamas and the tea and the chicken soup and the not going to work, I have the flu. So maybe you could try not being a complete berk this morning." The kettle was done. He turned and started making a pot of tea.
Seconds later, Sherlock's fingers wrapped around his wrist. John looked up and Sherlock was watching him, eyes narrowed, mouth set. John had to fight the urge to lean into him—he must be more ill than he'd thought, if he couldn't stand up on his own, although there was always the possibility that it was just his usual attraction to Sherlock, less well repressed due to the fever.
"Listen to me very carefully," Sherlock said. "You need to go upstairs, lock your door, and get into bed. You're going to feel even stranger than you do now in about half an hour, and I won't be back before then. If anyone comes by, don't let them in. I'll take care of them when I get home. Do you understand me?"
"What criminal mastermind did you piss off now?" John said. The tea would finish steeping soon, and then he could—
"John," Sherlock said, and actually shook him. John realised he was almost leaning into Sherlock's chest and frowned. "Do you trust me?"
"Yes," John said warily.
"Then do what I say. I'll be back as soon as I can."
"Okay," John said. Definitely a criminal mastermind.
Sherlock released his wrist and ran down the stairs. John took his tea up to the bedroom and locked the door.
***
Nobody tried to come in. John wasn't sure what particular phantoms Sherlock was afraid of, but they didn't materialise. Just as well, because John was in no state to either turn them away or let them in.
He tried to read the news on his laptop, but it was hard to concentrate. The sticky-hot feeling to his skin gradually gave way to chills and shivering—very not good, if his fever was going up again. He resolutely pushed the blankets to the foot of his bed and didn't tuck himself beneath them even though he really, really wanted to. Instead he closed his laptop and curled up on his side.
Gradually, he became aware of a—wetness—between his arse cheeks. "Fuck," he said, and the tone of his voice was surprising: rough and deeper than usual, like he'd been speaking a lot or breathing heavily. Still, diarrhoea was not what he wanted while he couldn't leave the bedroom, and diarrhoea he hadn't even felt was a bad sign indeed. He stood up, made a face at the slick feeling, and grabbed a handful of tissues to clean up what damage he could.
Sherlock had seemed like he knew what was about to happen. What had he guessed? Poisoning, John thought suddenly. From one of Sherlock's enemies, or one of his experiments, and he was going for the antidote— How did that square with what Sherlock had said about pills? John shook his head and wiped carefully with a tissue. When he pulled it out to throw it in the bin, however, it was clean.
No, John amended. It was damp. But with something clear. He sniffed it and it was strange, but not noticeably faecal. He grabbed another tissue and reached back, pressed—
It felt like somebody had triggered every nerve in his body all at once. He was on the floor before he knew it, tissue detectably wet beneath his fingers, and he was half-hard. His entire pelvis ached and waves of tingling were racing up and down the skin of his legs.
"Sherlock Holmes, you have a lot of questions to answer," John muttered to himself. He tossed the tissue in the bin, grabbed a handful to wad up in his boxers, and stumbled back to bed to try to not shake to pieces or let anything touch him below the waist before Sherlock returned.
***
Sherlock took an eternity to get home, or thirty-five minutes by the clock on John's bedside table. John's fingers were sore where he was clutching the pillow and he was back to sweating through his pyjamas—an improvement over the chills, if not by much. The wetness between his legs was growing by the minute. The sound of Sherlock's feet on the stairs to his bedroom was like a dozen angels singing.
"John, unlock the door," Sherlock said. He sounded more normal than he had in the kitchen. John pulled himself to his feet, gasped when he put weight on his arse, and staggered to the door.
Sherlock pushed it open as soon as the latch clicked; he got half a step in and stopped dead, staring. "Oh," he said. "I'm sorry, I—" He swallowed, and that tone was in his voice again, something repressed though not far enough. "I didn't mean to be so long," he said, which John didn't think was what he'd originally meant to say.
"Bloody right," John said. He was listing towards Sherlock again, so he closed the door and went back to bed, careful not to put any pressure on his backside as he laid down. "This explanation had better put all your other explanations to shame. I'm expecting the Olympic gold of explanations."
Sherlock nodded. His face was nearly expressionless, mouth closed resolutely, but his eyes were a little wide—Sherlock in full emotion-denial mode. "I brought you some medication." He reached into a knapsack John hadn't noticed and pulled out a large bottle. He put it on John's bedside table; it was full of diamond-shaped yellow capsules. John reached out to take it and Sherlock grabbed his wrist, took a deep breath, let it go. John could feel the impressions of his fingertips tingling on his skin. "You can't take them now. It would be...bad. In a few days."
John let his head fall back against the pillow. "What's for right now?"
"There's nothing for right now," Sherlock said.
John groaned and lifted his head up so he could knock it into the pillow a few times; it was satisfying, though not as satisfying as punching Sherlock.
"I'm sorry, you'll just have to ride it out. If I'd realised—" He closed his mouth so fast his teeth clicked.
"You're going to have to tell me sometime," John said.
"Yes." Sherlock looked at the bed, at the door, at the bed again, and remained where he was standing. "John, you're not human."
John laughed. "Funny, between the two of us I would have picked you for the android."
"I'm not human either," Sherlock said.
It wasn't sarcasm, the only type of humour Sherlock ever indulged in. John decided a little suspension of disbelief wouldn't kill him, at least not any more than his mystery not-flu. "So...what are we?"
"We don't really have a name," Sherlock said. "Also, you're probably only half what I am, although since you were adopted it's impossible to tell for sure."
"Half-alien. Excellent," John said.
"Not alien."
"Mutants?"
Sherlock looked around the room. "Near enough," he said finally. "Primarily, we differ from humans through our reproductive channels and certain inbuilt tendencies to lead or follow and to bond with others like ourselves, although that is obviously subject to the normal vagaries of our personalities."
"Hmm," John said. Full abstract explanation mode. He shifted on the bed, trying to ease the prickling sensation along his thighs, and Sherlock's eyes went to his groin as if magnetised.
Slowly, he dragged his eyes back up to John's face. "Some of us have a heat cycle, a time of peak fertility rather like an animal's heat." Sherlock licked his lips and John let himself appreciate it. "The sex drive increases and the chance of pregnancy is very high. The various hormonal surges can be distressing, I'm told, if there's no available outlet."
"You're told?" John said.
Sherlock waved him off. "Yes, I am not in that minority of the population, though it seems that you are." John nodded. Okay, yes, overblown sex drive—it wasn't like his usual horniness, he'd give it that, but the way he felt when his arse was pressed was undoubtedly sexual. "That medication will suppress the cycles in future, but it would be bad for your body to take them now. I had assumed you were taking them. You haven't gone into heat since you've been here, obviously, but if you are half-human it might have required a trigger."
John nodded. "And what was the trigger?"
"Ah—too much time around me." Sherlock looked away. "There are pheromone responses."
John laughed. "I feel like this because my body wants to jump your bones?"
"Yes," Sherlock said. He'd never looked so uncomfortable.
"Because...I think I can make you pregnant?"
John revised his estimate of how uncomfortable Sherlock could look. "No. Your body is capable of carrying a child."
John choked.
"Possibly," Sherlock said hastily. "If you're really a human hybrid it's possible you're infertile and this is just a vestigial hormonal response—"
"I don't know that that's better," John said.
"Anyway, this should last about three days. Maybe four since you clearly haven't done it before."
"Oh, God," John said. He shifted again to relieve the ache in his hip. Days of this?
"I suggest you masturbate as much as possible, it should take the edge off. I've brought you some aids, they're in the knapsack." Aids. Dear God. "Also a better lock for your door—I should install that now." He knelt down and pulled out some hardware and a screwdriver.
"Why do I need a better lock?"
Sherlock busied himself at the door. "Your pheromones are very strong right now. You're not used to paying attention to them but I can teach you once this is over—I know you can smell them, it's why you keep trying to lean on me." John blushed, even though he'd known Sherlock must have noticed. "This will keep out anyone who is attracted by them."
John stared at the bottle of medication. Every day for the rest of his life, or feel like this? Maybe he didn't have to—maybe if he didn't spend so much time with Sherlock—well, that was a ship that had sailed long ago. Pills it was. "Are we going to have random mutants wandering in off the street, then? How many of us are there?" Not that he believed it yet, but Sherlock clearly did, and either way there was something unusual wrong with him.
"Perhaps one percent of the population, perhaps less. It's likely if you masturbate that the pheromones won't be strong enough to attract alphas in off the street, no. And in any case the front door lock should be quite sufficient to dissuade them."
"Alphas?"
"Those like me who would be attracted to your pheromone signature and eager to help out."
Help out? Nothing like feeling like a charity case to dampen the sex drive. "What am I, then?"
Sherlock didn't answer for a moment. "Omega."
"First and last. Lovely."
"It's a name, not a value judgement," Sherlock said.
"And if I were to find myself in a community of people like us, would they agree?"
Sherlock jammed the lock against the door rather more firmly than necessary. "You should have been in a community. I don't know how your family let you be adopted by humans."
"I don't see you with a community very often," John said.
Sherlock bared his teeth at the door. "I choose not to let my life be controlled by hormone cycles or those who think I should defer to their judgement," he said hotly. "But it was a choice. You didn't get one."
John chewed that over. "All right," he said finally as Sherlock began to screw the hasp into the door jamb. "Why do I need to lock that, then? If no one's coming in off the street?"
"For me. When I leave you should lock it immediately. Don't worry, I bought one I can't break through before I have second thoughts."
Interesting. Did that mean he was—? John sat up, then gasped—oh, he was getting too sensitive.
"Please refrain from doing that while I am in the room."
"These pheromones can't possibly be strong enough to make you want to have sex with me," John said.
Sherlock licked his lips. "Not on their own, no."
"What else is there, then?"
Sherlock didn't answer. He tested the hinges on the part of the lock attached to the door.
John sighed. "I don't need a lock to protect me from you."
Sherlock stood up. "I'll be right back," he said and walked out.
John rolled off the bed ungracefully and walked over to the knapsack. His boxers were damp and disgusting, now, but he thought it would be a bad idea to take them off. If he was going to try to get Sherlock to have sex with him—and the idea was sounding better and better—he'd like to keep Sherlock as mentally clear as possible, in case he had regrets later on. Not that he thought Sherlock would have regrets; this conversation had been rather enlightening in that regard.
He pawed through the knapsack. The promised aids were inside: a dildo and a butt plug. No lube. He suddenly put two and two together and rocked backwards, which put pressure on places he didn't really want to and—yes. Okay. Body built to take it up the arse. "This is a fucking bizarre mutation," he muttered, examining the dildo. It had some kind of inflation pump attached to it. He pumped a couple of times with one hand, and a spot about a third of the way along the dildo began to inflate into a small ball.
There was another bottle of pills below the dildo, containing four fat capsules. John squinted at them, but there was no label, no way to tell what they were for.
Sherlock made a noise at the door and John stood. "Here's some water," Sherlock said, placing a couple of bottles just inside John's room. "I will be able to restrain myself long enough for you to use the toilet when you need to. But keep the door locked otherwise." He turned to leave.
John said, "What are the other pills for?"
"Birth control." Sherlock closed the door behind him.
Oh, as though could John leave that alone! He yanked the door open and Sherlock paused on the stairs. "Why did you buy me birth control?"
"It seemed prudent," Sherlock said.
"I'm not going to have sex with anyone but you, you idiot," John said.
Sherlock didn't turn, but John could see the side of his face, where his eyes had closed. Yes. He felt more and more certain the longer this conversation went on.
"That's the other thing, isn't it? You said 'not on its own,' but you meant you already wanted to." John was a little lightheaded, but he could make it down two stairs. Sherlock's eyes opened when John stepped in front of him. "Sherlock, you have to know I feel the same way."
Sherlock shook his head mutely.
"You're the most observant man I know, surely you've noticed," John said.
"You are compromised," Sherlock said. "Your body wants mine and you think it's your own volition but—"
John cut him off with a kiss. He had to pull Sherlock's face down fairly far, and he'd intended it to be demanding, but somehow it was slow and languorous, soft. Sherlock's eyes were trained on him when they broke apart, intent as though nothing else in the world existed. "I would've jumped you months ago if I'd thought you were interested," John said.
"I was," Sherlock said. He swallowed. "I am."
"Good. Come to bed."
"There's another conversation we need to have," Sherlock said as he turned back up the stairs.
***
"How big?" John said.
Sherlock grimaced. "My knot doesn't swell unless I'm inside someone, which makes it rather hard to take accurate measurements." John had to smile at how irritated that fact obviously made him.
"Maybe we can figure out a way to do that next time," John said. Sherlock perked up. "I think it will require more coordination than I have right now, though."
Sherlock nodded. "How do you feel?"
"Like I really need to see you naked," John said. The heat was catching up with him now. Even his boxers were too much sensation, rough against his skin.
Sherlock smiled a little and stood up. He didn't tease or delay, just stripped off his clothing efficiently. John's mouth went dry at the sight of him: thin, almost bony, but obviously strong, almost no body hair. His cock was enormous, standing away from his stomach, foreskin pulled partly back. John felt the strangest pull; he wanted it inside him now—and wasn't that an odd urge.
"Why didn't I get one of those?" John said.
Sherlock grinned. "You're getting one soon enough," he said.
John flopped onto his back and covered his face, giggling. "Whatever porn film you got that from, delete it," he said. He couldn't help grinding back into the mattress a little, now that he was finally getting some friction against his arse.
"Done," Sherlock said. "Will you take your clothes off as well?"
Politeness definitely deserved a reward. John kicked off his pyjama bottoms and pants and pulled the shirt over his head.
Sherlock climbed back onto the bed and over to him. "May I?"
John nodded.
Sherlock's hand closed around his cock and John bucked upwards, groaning. Sherlock leaned down to kiss him and that was even better; he didn't kiss like John had expected, instead going for a number of small presses of lips, long enough for their tongues to touch before he pulled away, coming back almost on the same undulating motion. John ran his fingers along Sherlock's chest and rode his hips up into Sherlock's hand until Sherlock took it away, slipping down behind his balls to press one finger inside him and that felt—Christ. John's body lit up like a Christmas tree. He let his head fall back to the pillow and Sherlock chased him down to suck on his tongue.
Sherlock withdrew the finger and John pulled back and blinked up at him, slightly fuzzy round the edges. "You need to fuck me right now," John said.
Sherlock kissed him again and then settled onto his back. "Come here, it will be easier for you."
John rolled on top of him and wriggled, enjoying the feel of skin all the way down, that magnificent prick sliding against his own. Sherlock's eyes went dark and surprised and he gasped. Lovely. "Just...slide on?" John said.
"Sit up and lower yourself," Sherlock said.
John manoeuvred himself upward. Sherlock grabbed hold of one hip and put his other hand between John's legs. Aiming himself, John thought. He sat back slowly till he could feel the blunt end of Sherlock's cock against his hole. It felt enormous, but at the same time John felt soft around it, like it wouldn't be that hard to take it after all. He bit his lip and met Sherlock's eyes, which—oh. Sherlock's mouth was open and glistening, from his spit or John's, and he looked completely out of his mind with lust. John sank down, keeping his eyes locked on Sherlock's, the electricity from that almost more shocking than the pressure in his arse. The stretch of it was odd, and John pushed out against it, trying to ease the ache, which was enough to get Sherlock inside him. John gasped and clenched and Sherlock groaned; his hand came up and rubbed John's lower belly, and John knew he couldn't possibly feel himself inside but even the thought of it—he rocked back and more of Sherlock's cock sank in and Sherlock threw his head back on the pillow, revealing the long pale column of his throat.
John folded forward and took a deep breath right at the juncture of Sherlock's neck and shoulder, then kissed the spot. "John, please," Sherlock said, the strain in his voice vibrating through him to John's lips, and John slid down as much as he could. Sherlock was huge but John wanted it, too, more than he was scared of it. He sat up and tried to settle back, to let gravity do the work.
Sherlock's eyes were as wide as John had ever seen them, hands still on John's body like he was afraid to let go. John shifted up and down, just slightly, just a little, and Sherlock's fingers tightened on his skin. He felt entirely surrounded. "Not going to last very long," Sherlock said.
"Me either," John said.
"I was talking about you," Sherlock said. John laughed, and Sherlock smiled. "Here, if you hold yourself up—yes, like that, good, John," he said, and thrust up into him.
John fell forward a little and braced himself on Sherlock's shoulders; it was easier if he didn't have to move, the strain in his thighs was too much with everything else coursing through his body. But Sherlock was doing the work now, sliding in and out. John was getting used to it, to the feeling of it and how much he wanted it, and it was...brilliant. He started stroking his dick and, there, yes, exactly what he wanted. "Really not very long," he said, breathless.
"Yes. We could stop," Sherlock said, panting. There was a fine sheen of sweat all over his chest.
"Are you joking?" John said. "Don't bloody stop!"
Sherlock grunted and thrust up hard a couple of times, then pulled John down onto his cock and started circling his hips instead. Still felt good, though—though maybe—something different—
John realised what was happening a split second too late to stop it. The knot was expanding within him, a sort of irresistible pressure right against his prostate. He tried to lift up a little and pain blossomed all around his hole—shit, no, okay.
Sherlock's face was red now, his eyes bright and hectic, tongue wetting his bottom lip again and again. "Sssh, John," he said. "Just relax."
John tried, but his cock was so, so hard and his fingers just weren't enough. "Your hand," he said, "please," and Sherlock's fingers joined him, wrapped around his shaft and tugged hard and John saw stars as he pulsed onto Sherlock's stomach. Sherlock thrust again and John found another spasm and another—the sheer volume of it was shocking, more than he'd ever come in his life.
He felt like a teenager, coming so fast, but he couldn't be embarrassed when Sherlock looked so utterly destroyed too. He was aware, suddenly, that he'd been wound tight since he woke up; it had felt natural till it was gone, and now he was loose, boneless, strangely clearheaded. And the knot was still getting bigger inside him. He tried to move again and that was worse. He made a noise and Sherlock flipped them, which was very sexy but not at all better, and tucked John's face into his neck. "I'm sorry, I'm sorry," he said. Apology from Sherlock Holmes: amazing what it took to get one. "Almost there. God, John, how you looked."
John brought his arms up to wrap around Sherlock's torso. This close he could hear tiny moans that Sherlock wasn't letting out of his throat, and his hips were shifting restlessly where they were pressed against John's arse. The pain was there but he was adjusting, more muscle-cramp aches than anything. Sherlock groaned and went still and John rolled a little till he could see Sherlock's face, mouth slack and eyes slammed shut, still that surprising colour splashed along his prominent cheekbones.
"That's it," John said softly, rubbing one hand up and down Sherlock's spine. Bizarre anatomy aside, John was sure he was more used to this sort of thing than Sherlock was. He kissed the side of Sherlock's face. "Feels wonderful," a tiny harmless lie.
Sherlock's eyes opened and he turned his head to kiss John again, those same lazy half-drunk kisses that hardly seemed to end. John wound one of his hands in that marvellous curly hair and Sherlock petted John's sides. "We should have done this ages ago," John said when they parted.
Sherlock's mouth twitched in a small smile. "You would have got quite a shock," he said.
"You wouldn't have explained?"
"I though you knew."
"Well, I didn't," John said.
Whatever Sherlock was going to say was interrupted by another groan and the press of his cock a fraction further into John's arse. "That's just bloody unfair," John said. "How many times do you get to go off?"
"Fifteen to twenty, usually."
John tried to figure out how long that was going to take. A while, anyway. He rubbed one foot up the back of Sherlock's long leg. "Unfair."
"Well, you'll be in your right mind, while every so often I will be robbed of coherence," Sherlock said, annoyed. "Until we separate. Then your heat will take over again."
"So we'll trade off clarity of thought," John said. "At least one of us'll be responsible at any given time. That's handy."
"Yes, and for once you'll get to be the clearheaded one some of the time."
John squeezed around Sherlock's prick and Sherlock choked and buried his face in John's shoulder. Oh yes, this was going to be fun. John was starting to get hard again where he was snugged up against the firm muscles of Sherlock's stomach. That was a fairly startling refractory period for a man of his age. "Three days?" he said.
"Four, probably," Sherlock said. "They don't normally start quite this suddenly. Being knotted early on will help, though."
"Hmm," John said. "You're assigning a lot of power to your dick, there. You don't really seem the type."
"I'm beginning to suspect the knot was developed before we became verbal as a species," Sherlock said into his shoulder.
John grinned. He was feeling remarkably better now, sated and happy and sticky and great. "Nothing's changed. You were already stuck with me," he said, and smiled.