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betting on the unexpected

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"Derek," says Stiles, because well, that's a knot, a fucking werewolf knot, and excuse him for thinking they were in the clear about that whole thing because of how they've been having sex already, and lots of it. "Derek, what the fuck, what is-- "

"Shut up," says Derek tightly.

Stiles bites down on his lip for all of three seconds before he bursts out with, "You couldn't have warned me?"

"I didn't know," said Derek.

"What?" says Stiles. "What? It's-- that's your dick, dude, like, your own private personal penis, how could you not know it did-- that?"

"Because it's never happened, obviously," says Derek.

"Okay," says Stiles, even though it really isn't, come on. "Okay, that's-- okay. Do you have any, like-- theories, or, or arcane werewolf knowledge about…that?"

"I've heard," says Derek, and then stops.

"Heard what?" says Stiles.

"Nothing," says Derek. "We should stop."

"Hell no," says Stiles, grabbing a precautionary hold of Derek's hips even though that's pretty useless if Derek actually tries to get away. "It took for-fucking-ever to get you to have sex with me, okay, I'm not going to be put off by much. It's just a surprise, I mean. Come on. It's not like this is the first time. I thought if there was anything I'd know about it by now."

"So did I," mutters Derek.

"Okay, so come on, theories, I love theories. What have you heard?" says Stiles encouragingly.

Derek looks physically pained. Huh. Maybe it hurts him? Or maybe not, Stiles revises when Derek says, "I've heard-- I mean, I thought it was a joke, but-- when it's your. Your mate." He shrugs.

Stiles just blinks at him stupidly for a long second. "Hang on," he says eventually. "Just hold up, hold everything, is this-- does your dick think I'm your mate? Is that what's happening here?"

"We should stop," says Derek again.

"No," says Stiles.

Derek looks at him then, finally. "Stiles," he says, and great, that's his you're an idiot who doesn't know when to quit voice, "Are you really okay with-- with that? Never mind with mate."

"I'm flattered, actually," says Stiles challengingly. "Your dick thinks I'm your mate. That's-- that's kind of sweet, right? More than I can say for the rest of you, anyway."

"Stiles," says Derek warningly, and that's brilliant, now he's starting to sound pissed.

"What, what?" says Stiles loudly. "Come on, it's not that bad. Like, I can take it, dude. You're not that big, even with that thing."

"Thanks." Derek rolls his eyes.

"You know what I mean," says Stiles. "Unless this is-- are you pissed? Like, at your dick? Do you not want to be my mate?"

That comes out a lot more desperate than Stiles would ideally like, shit.

"This conversation is not happening," says Derek, closing his eyes like if he does that somehow it won't be.

"Sorry to burst your bubble, sour wolf, but it kind of is," says Stiles. "And might I remind you the reason we're having it in the first place is your dick."

Derek's mouth tightens. Stiles feels kind of bad.

"I mean, not that-- it's not your fault, obviously you can't help it," says Stiles. "Hey, I told you, it's totally a compliment! I'm flattered. Not freaked out. At all. Well, okay, maybe a bit startled, but-- "

"Stiles," says Derek.

"Yeah, okay, shutting up," says Stiles.

"No, just." Derek opens his eyes and shakes his head. "This isn't helping."

"Well," says Stiles, "You wouldn't answer any of my totally helpful questions, so I-- "

"Yes, okay," says Derek loudly, looking away like this is the last thing on earth, including fighting psychotic hunters and emotionally fucked-up were-lizards, he wants to be doing. "I want to be your…that."

Stiles gapes at him. "Oh my God," he says.

"Shut up," says Derek.

"Oh my God," says Stiles.

Derek breathes out sharply. "I'm going to get dressed," he says.

"Don't you dare," says Stiles. "You said it, okay, you don't get to-- to take it back or run away til you're okay with having feelings, or."

"I didn't-- "

"Okay, your dick said it for you, whatever." Stiles waves a hand.

Derek stares at him all intense or whatever. "This is ridiculous," he says at last.

"Kind of," agrees Stiles. "Look, I-- if you're seriously not ready for-- for that, I-- we can forget about it, okay, I can totally pretend it didn't happen. If I get distracted enough I might even genuinely forget."

"Stiles," says Derek, and he leans back down over Stiles, one arm braced on either side of Stiles' head. His eyes get even more intense, if that's possible; apparently it is, because they flash red for a second before going back to their usual dark and scary. "Every time you smell even remotely like someone else, I want to find them and rip their throat out."

"Um," says Stiles. "That's-- so that's good, I mean. Isn't it?"

Derek watches him a minute longer. "You're sixteen," he says.

"So?" Stiles blinks.

"So you're young. Too young to think about…that. About being someone's…mate."

"What," says Stiles, "So if I wanted to go, like, bang a cheerleader or something, you'd be okay with that?"

Derek raises an eyebrow.

"Shut up, dude, suspend belief for a moment and pretend I could bang a cheerleader."

"…Yes," says Derek eventually.

"You're lying," says Stiles.

Derek frowns.

"That's not a bad thing," says Stiles. "Like, I would be having concerns about the state of our relationship if you were okay with me banging cheerleaders. Or anyone."

Derek says, "This isn't," and then stops.

"Yeah, I don't think you can get away with saying this isn't a relationship two minutes after you just admitted you want me to be your mate," says Stiles. "Unless that means something else in werewolf speak."

"It doesn't," says Derek. He sounds pretty unhappy about it, actually.

Stiles rolls his eyes. "Dude, seriously, I'm not sure this qualifies as a bad thing," he says. "Like, I know it might be hard to accept because of how your life is generally pretty shitty, but this is good, okay."

"Is it," says Derek flatly.

"Are you trying to give me a complex?" says Stiles. "Do you or do you not want to be my mate? Also, I'm going to veto that word because it's seriously too animal kingdom for me. So we're going to go with boyfriend instead."

"That's too highschool for me," says Derek.

"Yeah, well, deal with it," says Stiles snippily. "I am in highschool."

Derek rolls his eyes but doesn't say anything.

"So," says Stiles. "Boyfriends, yes or no?"

Derek stalls a long time before he says, "Yes," grudgingly.

"Great," says Stiles. "Brilliant, excellent, okay. Can we go back to the fucking now?"

Derek kind of…looks really eloquently down at his dick, which. Oh. Yeah. Stiles had kind of forgotten.

He's not sure how, looking at it again, because it's like…there. This knot. That apparently is supposed to fit inside him, and even though he'd been all blasé about it to Derek a second ago it's still kind of intimidatingly huge-looking. Like, Derek's dick isn't small to begin with, and add to its normal girth the current swollen state of the base, and…well.

"Lube," says Stiles eventually. "We're going to need more lube."

"Seriously?" says Derek.

"I-- yeah." Stiles swallows. "Unless-- you want to, right?"

Derek's got his yes but I don't want to admit it look, so that's. That's good.

"Okay, great, so let's do this," says Stiles. "Come on, this is just like the first time when you didn't want to put your regular-sized dick in me. Look how awesomely that turned out."

"Shut up," says Derek. "I just. I don't know what else will happen. Obviously."

"Um," says Stiles. That's a really good point he's got there. "We can-- I mean, it can't be bad, right? It's just a dick. I'm pretty sure if it had, like, Wolverine-style appendages in there you'd definitely know about that."

Derek looks doubtful.

"Oh my God," says Stiles loudly. "Okay, I'm making an executive decision to be the voice of reason here. Your dick does not have claws or fangs or anything freaky that will hinder as opposed to help and like, make awesome, the process of sex. So let's go, buddy, let's do this. I want to like, accept your knot. Also, I immediately regret saying that."

Derek still looks pained, but it's tipping towards his I can't believe I'm associating with such an idiot pained, as opposed to his genuine my life is constantly and never-endingly terrible pained.

"Can I-- can I touch it?" says Stiles. That seems like a good, safe place to start.

Derek is silent for a long moment, and then he says, "Yeah," all tight and hoarse.

Stiles reaches out to curl his fingers around the end of Derek's cock, which is still its same familiar size and shape. He lets them wander down to the base though, the tips of them brushing over the oh-so-swollen flesh there. Derek hisses in a breath, and Stiles thinks he probably would've twitched or something if he wasn't, like, made of discipline.

"Does it," says Stiles curiously, swallowing. "Does it feel different?"

Derek shakes his head. "It feels like more," he says.

Yeah. Stiles gets that. It's kind of the same from his end, like, the skin there feels the same, impossibly soft and thin and blood-warm, but it's so swollen under his fingers, he can feel the pressure there, and the heat as well, sort of similar to how it usually is but just more.

"Wow," says Stiles. "Okay, do you want to-- with your fingers, or, or should I?"

Derek growls and shoves Stiles' hand aside so he can get two fingers back inside him without warning, and Stiles arches his neck back, biting down on a groan.

"Fuck yes," he says. "Come on, you know I love it when you-- oh, yeah." He bites down hard on his lip when Derek adds another finger.

"Another?" says Derek tightly.

Stiles thinks about it. They usually go from three to Derek's cock, and Stiles likes it that way, he likes the always unexpected stretch of it. "No," he says. "Just. More lube. And we can-- we don't need a condom, right?"

Derek stills entirely. "Stiles," he says.

"What?" he says. "I'm not-- you know I was a virgin when we-- when we started this. And you-- I mean, unless there's something you're not telling me, you're clean, right? Can werewolves even get STIs, actually?"

Derek's got that annoyed look he gets when he doesn't know something, but he says, kind of grudgingly, "I'm clean."

"So what's the problem?" Stiles blinks at him.

"I," says Derek, and stops. "That's," he tries again, and stops again.

"Awesome," says Stiles. "So, no condom. Also fucking Christ can you start moving again because I'm dying over here."

Derek twists his fingers kind of absently.

Stiles gasps and pushes down with his hips and snaps his fingers in front of Derek's face. "Hello, yes, I'm still here waiting to get fucked, can you pay attention?"

"I am paying attention," says Derek, and reaches for the lube with his free hand.

"Good to know." Stiles rolls his eyes and watches as Derek pours a serious amount of lube onto his dick and also his fingers, pressing it into Stiles, so wet, Jesus.

"Are you-- sure?" says Derek, and Stiles would say it sounded almost hesitant if it wasn't Derek talking.

"Hell yes," says Stiles. "Do it, come on. Although actually, no, c'mere first."

"What?" says Derek, eyes snapping to his face.

"Kiss me," says Stiles.

Derek pauses a moment before leaning in, but then it's wet and thorough and so fucking intense when he kisses Stiles, like it always is, his stupid soft mouth and his grating stubble driving Stiles crazy, and Stiles grapples for a hold on his shoulders, just opening his mouth and taking it when Derek licks inside and practically fucks him with his tongue.

It's how Stiles figured out Derek wanted him in the first place. Like, he never says it-- or never until now, anyway-- but when he kisses Stiles it's all there in the way he presses in and cups his hands over Stiles' jaw and almost aches into it, like this is the best way he has of showing Stiles that he wants, too.

"Ugh, fuck you," says Stiles when Derek pulls away.

Derek actually smirks at him, which, yay, progress. "I thought I was supposed to be doing the fucking," he says.

"You're so smart," says Stiles, pressing down on Derek's fingers. "I knew I kept you around for a reason."

Derek rolls his eyes but doesn't say anything, which is kind of, like…Stiles knows that somewhere in there Derek actually appreciates that Stiles gives him shit all the time, and like, pushes back when Derek gets too hopped up on Alpha endorphins or whatever. He suspects it's part of the reason this thing between them is even happening, but whatever, he can think about that later, sometime when Derek doesn't have three fingers in his ass and needed to be fucking him, like, yesterday.

"Derek," he says, a bit embarrassingly breathily, "Derek, come on."

Derek pulls his fingers out abruptly, and Stiles gets halfway through a whine before Derek's pushing back in with his dick, all the way to where it starts swelling into his…his knot, and then he stops.

"Fuck, oh fuck," babbles Stiles, twisting his hips, trying to get used to the feeling of being filled like this, which he still hasn't, and they've done this a lot. He kind of hopes he never will.

Derek pulls out and pushes back in, and it's fucking awesome like it always is, but he stops again.

"Derek," says Stiles.

"Shut up," says Derek, and Stiles rolls his eyes.

"Do you always mean to say that?" he says curiously, "Or do you just, like, open your mouth and 'shut up, Stiles,' is what comes out? Like an unconscious response or something. Which is, hmm, I don't know how I feel about that, it's kind of-- oh. Fuck."

Derek's fucking him in earnest now, and he still hasn't pushed all the way in but Stiles can feel the swollen base of his cock pushing at him every time he thrusts in, and it's-- it's almost as good as having it inside him, maybe, like, obviously he doesn't know, but he likes that, the dizzying sense of promise, like when Derek makes him wait with just the head of his cock nudged up inside him.

"Stiles," says Derek.

"Yeah," says Stiles on a breath.

Derek shakes his head and wraps a hand around Stiles' cock, which Stiles had actually forgotten about, in an abstract kind of way where he never really forgets his dick is there, because…hello, teenage boy, his dick is always somewhere in the back of his mind. Well. Figuratively, anyway.

"Oh God," says Stiles. "Fuck, your fucking hands, don't stop."

"Mmm," says Derek. "Wasn't going to."

"Do it," says Stiles, trying to push onto Derek's cock with his hips. "Come on, I want it."

"Stiles," says Derek, and it's like, Stiles doesn't think Derek actually has a point, and that's hot in itself, like, everything about this situation is fucking hot, and Derek gritting out his name all purposeless and desperate is no exception. In the end Derek just says, "I need-- " and fucking does it, just pushes all the way in, finally, and…fuck. Fuck. Stiles shouts out and feels his spine arch so hard it could snap any second, feels Derek inside him, and it's just…it's so much, almost too much, and it hurts, of course it does, but Stiles, well, he's all about too much, isn't he, all about never knowing or caring where the lines are.

"Fuck," hisses Derek, holding himself still, and his arms are actually shaking. "Stiles-- "

"I'm-- I'm good," says Stiles, voice wavering.

"Yeah?" says Derek.

"Yeah," says Stiles. "Oh my God, I just-- move, Derek, come on."

Derek growls and does, not thrusting so much as grinding into him, and he takes his hand off Stiles' cock to curl over his throat instead, thumbing at the spot between his collarbones where his pulse is fluttering like crazy.

Stiles whines because that's-- he needs friction, goddamn it, even though he likes it when Derek spreads his hands out over his skin just to touch, but then Derek presses closer so he can get to Stiles' mouth and his stupid, perfectly sculpted abs rub up against Stiles' dick and oh hell yeah, that's it.

He moves his hips, lets himself really feel the way Derek's cock is pushing at his insides, filling him up so completely, the way his own cock is leaking and wet and trapped between them, and it's just-- he can't even think, it's just this insistent, white-hot hum under his skin, drowning everything out except Derek, except for how he needs to come, needs more, more, fucking more.

He gets out, "Derek," and then Derek bites down on his neck and that's it, that's all Stiles can take before he's coming, digging his nails into Derek's shoulderblades and muffling his noises against Derek's temple.

"Oh holy-- Derek, fuck, fuck, you've gotta be close, right? Fucking come, I want you to, I-- "

Derek groans and slaps a hand over his mouth and bites down on his own wrist when he comes, and that's-- wow, he's never done that before.

It makes Stiles wonder just what it feels like, and also is kind of insanely hot.

He realises belatedly but no less awesomely that he can feel it, too, like, obviously he always can but Derek's not wearing a condom this time, is he, and Stiles can feel it when he comes, he can feel the rush and the heat and the way it jerks through his cock, the way he grinds it into Stiles like he can't help it, just keeps pushing and pushing even when he must be-- he has to be spent.

"Oh my God," says Stiles eventually. Derek hasn't moved except to slump with all of his weight on Stiles, and Stiles maybe can't breathe, just a little bit, but he figures he's good for a while longer. If Derek wants to lie on top of him, Stiles isn't going to say no. He's not stupid.

Derek hums agreeably into his neck.

"I was so right," says Stiles, grinning.

"Actually, there's one thing I didn't think of," says Derek after a minute, and he doesn't sound too happy about it.

"What?" says Stiles. "Come on, don't ruin the moment, that was awesome."

"You know I can't actually move, right?" says Derek.

"What?" says Stiles. "Did you pull something?"

Derek lifts his head to give him his best you're a moron look. "I can't," he says slowly, like he's talking to someone particularly stupid, "Move."

"I know, you just-- oh. Oh. Um. Shit." Stiles blinks at him, because…yeah, that is a bit of a problem. Or well, not an immediate problem, but it definitely could be. Potentially.

"Yeah," says Derek flatly.

"Shit," says Stiles again. "That's-- should we have, like, tried a different position, maybe?"

"I don't think that would make a difference," says Derek.

"No, but. I just mean-- I'm okay for the moment, but dude, you're kind of heavy."

"Oh." Derek ducks his head to look down between them, then anchors Stiles with a hand on his back and rolls them over. "Better?"

"Um," squeaks Stiles. That's-- he can breathe now, sure, but Derek is still inside him and it's…doing interesting things to his dick. "Yes?"

"Good," says Derek. He folds one arm behind his head and keeps the other tucked over Stiles' back. "Go to sleep."

"That's-- really?" says Stiles. "I mean, how long will it take to…go away?"

"I don't know," says Derek.

"Okay," says Stiles slowly.

"Go to sleep," says Derek again.

"I," says Stiles. Derek is unbelievably warm everywhere they're touching, and like, it's not a bad feeling, his dick still inside Stiles. It's like, weirdly comforting. With this quiet, background buzz of turned-on, but Stiles could probably sleep before he deals with that, so, "Yeah," he says, tucking his head into the curve of Derek's muscles over his shoulder. "Okay."