Derek should have never given Stiles the book.
And sure, he’d had to twist Derek’s arm a little bit—because he was still taking intro-level classes, he only had a few of acquaintances on campus, and his little apartment, which had once seemed wonderfully private, now felt empty and lonely. He was bored.
So he’d called, texted, begged Derek for something to do, for something to help keep him in the supernatural loop. Derek had eventually agreed to lend him some research material, if Stiles would promise to leave him alone for an entire week.
It was a good deal, and Stiles had agreed to it readily. And, possibly against Derek’s better judgement, the first book he’d given Stiles was an old and very thorough tome on werewolves. An illustrated one, which was nice, because sometimes he got tired of squinting at the tiny print, and liked stare at the pictures for a while instead.
He’d immediately driven the hour back to Beacon Hills to get it, and had also gotten a half-hug from Derek, who didn’t seem to be nearly as annoyed as he’d pretended to be.
Stiles had started reading as soon as he’d returned to his apartment, and it all had been fine until he’d gotten to chapter fifteen. It was titled Werewolf Mating and Reproduction, and of course he’d been intrigued, considering how often werewolves had starred in his masturbatory fantasies.
And it was very interesting reading, especially one particular tidbit of information. According to the book, male born werewolves had something special that bitten wolves didn’t: a knot.
At first, reading the description, he was a little weirded out. It sounded so strange, having a penis with a base that enlarged during sex. He figured it must be uncomfortable too, being stuck together like that. Who would be into that?
When he flipped to the next page and saw the illustrations, he was unprepared for the pulse of arousal that went through him. The first one showed a ‘traditional mating,’ with a male werewolf knotting a female werewolf. Her claws were digging into his back, her head tipped back in pleasure and her hips lifting eagerly toward his.
There was a close-up drawing showing the way his knot fit inside her body, and Stiles peered at it interestedly, reading about the way it added to both of their pleasures during sex.
The next illustration, of a ‘non-traditional mating’, was detailed enough to get him hard in his pants. One male werewolf was mounted over the other, bodies pressed tight together and held by his claw-tipped hands. The werewolf on the bottom was stroking his hard cock, his face a picture of ecstasy.
Fuck, he thought with horrified embarrassment, I’m into it.
Really into it, it turned out, as he read more about knotting in male-male pairings and abruptly realized he was cupping himself through his jeans. And when he saw the note mentioning that a knot could result in multiple orgasms, a spike of arousal went through him, because making someone come more than once was one of his major turn-ons. (And one of the reasons he went down on girls so often.)
He unzipped his pants and began to stroke himself as he imagined Derek fucking him, his knot filling Stiles up so perfectly, and both of them rocking together until they came. He was just picturing Derek’s second orgasm when his own hit him hard, his body clenching around nothing as he worked himself through it.
He needed to talk to Derek.
“You said you have some questions?” Derek says as Stiles lets him into his apartment.
“Yeah, just a few,” Stiles says, taking a seat on the couch, and feeling relieved when Derek sits next to him. “About this section in particular.”
He picks up the book, and though he’d originally planned to ask some general questions about of the earlier chapters first, to lead up to his awkward sex questions, he figures he should just get to the point. Derek can probably smell the arousal on him, anyway.
He flips it open to the page he marked, and says, “I have some questions about knotting.”
Derek raises his eyebrows. “The book was very thorough,” he says, and Stiles hates that he’s not surprised at all. “What else do you need to know?”
“Have you ever knotted someone? What’s it feel like? Does it really last for thirty minutes? Do you like it? Would you knot me?” That last one gets out before Stiles can stop it, and he feels himself flushing.
Derek smirks, glances at the open book, then looks back at Stiles. “You know the knot is only intended for other werewolves, right? You might not be able to handle it.”
Stiles reels back a little, eyes wide. “Is that a challenge?”
“No,” Derek says immediately, obviously familiar with Stiles’ reaction to challenges. “I’m just saying that if you get knotted, and you’re not ready for it, you could get hurt.”
“Well, I’ve taken some pretty big dildos,” Stiles says confidently, and then realizes that’s probably too much information, considering the flush that’s spreading across Derek’s cheeks. “So I’m not worried about it,” he finishes awkwardly.
“Okay,” Derek says, voice sounding a little strangled. “You’re clearly set on this. There’s several options for who—”
“The book says only born wolves can do it,” Stiles cuts in. “And no way am I letting your creepy uncle knot me.”
Derek makes a face that shows he clearly agrees. “Sometimes bitten wolves do end up with a knot, but I haven’t gotten any horrified phone calls from Scott, so I’m guessing he doesn’t have one,” he says, amused. “But I’m in contact with several other born wolves—”
“Derek, I want it to be you,” Stiles blurts. “Not because you’re the only one around, not because it’s convenient, but because I like you. Because I trust you. And sure, you’re helping me assuage my, um, curiosity, but I’d want to have sex with you even if there’s no knot involved.”
“Stiles, we’ll literally be stuck together for at least twenty minutes. Are you sure you want that? With me?” Derek asks, looking serious now.
Stiles grins. “That actually sounds like a perk, to me.” And that’s all he gets out before Derek is kissing him.
Derek seems more than happy to just make out with him on the couch, but Stiles would really like to move this somewhere a little more comfortable. “Come on,” he says, tugging at Derek’s shirt. “Bedroom.”
Derek laughs at him, but Stiles muffles that with another kiss, guiding Derek down the hallway. He’s only too happy to undress Derek, savoring every bit of skin revealed, until Derek is fairly growling with anticipation.
He’s much hastier in getting Stiles out of his own clothes, though he makes up for it by immediately putting his hands and his mouth against Stiles’ skin. He drops to his knees to take long licks at Stiles’ cock, and then, just when Stiles is getting into it, wraps his hands around Stiles’ hips and tosses him on the bed.
“Whoa,” Stiles says, grinning when he bounces a little. “Wasn’t expecting that.”
Derek shrugs. “I’m gonna have to spend a while stretching you open, so I figured I might as well get started.”
Stiles swears he sees a hint of fang when Derek says that, and he feels a flare of arousal. This is really going to happen. He spreads his legs invitingly, and tries to smother his laugh when it makes Derek fumble the lube.
Then he’s back between Stiles’ legs, a slick finger sliding inside him as Derek’s mouth closes around his cock. At first, he’s tensed up, trying to move into each sensation, rocking into Derek’s hand as he arches against Derek’s tongue. But as it goes on, with Derek seeming tireless, he begins to relax into it, letting the waves of pleasure wash over him.
He floats like that for a while, but when Derek starts kissing his hips and thighs, three fingers spreading inside him, Stiles finally pants, “Derek, I’m ready. Seriously, so ready.”
He feels like he’s in danger of coming before Derek even gets a chance to knot him, and that just won’t do. He takes a couple of deep, calming breaths as Derek gently pulls his fingers free, trying to ground himself.
When Stiles cracks his eyes open to sneak a peek at what Derek is doing, he sees him slicking up his cock, so slow and careful it’s almost sensual, and he groans low in his throat.
But then Derek stops touching himself, and seems to hesitate there between Stiles’ knees. So he says, “Do I need to—would you rather I be on my stomach?” and then leans up on his elbows, ready to turn over.
Derek gives him a smile that looks a little nervous, and lays a tentative hand on Stiles’ chest. “No, I’d rather do it like this,” he says softly. “If that’s okay?”
“Yes,” Stiles says, tugging on Derek’s shoulders and kissing him when he settles down against him.
He can feel Derek’s hard cock against his thigh, and it sends a hot pulse of excitement through him. He wiggles a little, eager, and Derek obviously gets the hint, because he curls his hips in, the head of his cock brushing Stiles’ entrance.
Stiles lets out a shivery little moan when Derek finally slides in, and he feels Derek smiling against his lips. He starts to move in long, smooth thrusts, sending pleasure sparking through Stiles. Derek gives him one more kiss, then he drops his head and opens his mouth against Stiles’ collarbone, teeth gently grazing his skin.
Unlike Stiles, who is trying to stay relaxed and is mostly succeeding, Derek seems drawn tight, the muscles of his shoulders tense beneath Stiles’ hands. He’s holding himself back, Stiles realizes, trying to keep his pace steady.
But Stiles is aching, is longing, for more, so he braces his feet on the bed lifts himself a little to meet Derek’s hips, and slides a hand down to squeeze Derek’s ass encouragingly. He gets a low growl for his efforts, and Derek is suddenly speeding up, keeping his movements close and tight, driving into Stiles just the way he wants.
It’s giving him a fluttery feeling like he’s getting close to the edge, and he’s pretty sure if he touched his cock now, he’d come instantly. “So, um, when does it happen?” he asks, partially to distract himself, and partially out of pure curiosity, because obviously this has never happened to him before.
“Soon,” Derek says, low. “You’ll know.”
Stiles can’t imagine that could be true, but when Derek wedges his hands under Stiles’ hips and switches from thrusting to a desperate sort of grinding, making a soft rumbling sound as he does, he’s pretty sure he knows what’s happening.
A spike of anticipation goes through him, and he tightens his arms around Derek just as he tries to push deeper. Or at least, that’s what it feels like at first. But then he realizes he’s being stretched open, that Derek’s knot is filling him up.
Derek is keening now, his whole body trembling as he surges forward against Stiles, and then he’s coming, his body curling around Stiles as he does. Derek’s knot feels like it’s pressing directly on his prostate, and he shifts around as the sensation becomes overwhelming, unable to keep still.
He rolls his hips a little, looking for some kind of relief, and his orgasm hits him abruptly as he clenches tight around Derek. But that only helps for a few moments. Derek’s shuddering above him, clearly coming again, bucking up into Stiles as he does, and the feeling of that knot moving inside him pushes Stiles right back to the edge again.
He finds his thighs clenching against Derek’s sides, his hands digging into Derek’s shoulders, and thinks wildly I thought he was supposed to be the one having multiple orgasms, not me, before he’s jolting against Derek and coming again.
He’s sort of afraid they’re going to become some sort of perpetual orgasm machine, with Stiles’ orgasm triggering Derek to come, and then Derek’s orgasm getting Stiles off, and so on for eternity, or at least until they both pass out.
But after his third orgasm—and possibly Derek’s sixth, he lost count—he feels both wrung out and entirely stated, and knows he won’t be coming again for a while. When his muscles stop twitching, and he starts to catch his breath, he finds Derek kissing and nuzzling his neck and jaw, his hands stroking along Stiles’ back and sides.
He’s still at the low end of his orgasm, Stiles realizes, when Derek’s hips gently rock forward, and he feels Derek’s knot pulse inside him. It’s a huge turn-on, but only in his head, because his dick doesn’t even try to respond.
All the orgasms have made Derek very soft and pliant, and he makes a pleased rumble when Stiles tentatively traces his hands along his shoulders and the back of his neck.
Derek keeps touching and licking and kissing Stiles as he rides it out, and Stiles can’t help thinking that this unguarded affection is probably the best part of the whole thing.
Eventually Derek settles down, warm and heavy, on top of him, taking deep breaths but otherwise staying perfectly still. Stiles carefully rests his hands on Derek’s lower back, wondering if he’s fallen asleep. He can’t tell if Derek’s knot has gone down, or if he’s just gotten used to it, so he tilts his hips a little. He feels the familiar tug of it, just as Derek makes a quiet sound and shivers a little. It’s still there then. That’s okay with Stiles though, he’s perfectly happy to stay here, just like this.
Derek eventually rouses a little, lifting his head to look at Stiles. “You okay? It’s going to be a little while longer.”
“I am more than okay, that was amazing,” Stiles says, giving Derek a smile that is likely pretty dopey. Then his stupid mouth says, “Seriously, can we make this a regular thing?” and he winces.
But Derek just gives him a soft kiss and says, “I’d like that.” And maybe sexual intimacy leads to more personal intimacy, because he goes on to say, softly, “I haven’t knotted someone I actually trust in a long time. I forgot how much I liked it.”
That makes Stiles’ heart ache for Derek, and he’s suddenly so glad Derek is here, tangled up in his sheets, safe and happy. He doesn’t know how to say that, though, so he just kisses Derek again, hoping that the press of his lips, and the gentle touch of his fingers against Derek’s skin, will tell him how he feels.
Derek kisses him back so sweetly, with one hand softly cupping Stiles’ jaw, that Stiles knows he understands.