Cora missed the start of the conversation, and really has no idea how it could possibly have come up naturally , except that her brother and Stiles are like, stupidly into each other and way in denial, so maybe one of them is finally figuring it out and decided to just throw it out there. But, however it came up, it was impossible not to hear Stiles’ over excited “Dude, I'd totally be the top if we had sex,” as she walked by Derek's closed bedroom door.
Derek’s answering “No way, man. It'd definitely be me, I mean I know it's not how these things are decided, but my dick is bigger, so..,” is so indignant and almost squeaky with what Cora can only assume is the realization that he's now thinking about his best friend's dick, that she has to stifle a giggle. There is no way she can leave now, and miss the disaster that must be coming; the inevitable gay-panic or the realization that they are totally in love will give her blackmail and ammunition for months, so, she slides down next to Derek's door, leans against the wall, and listens.
She is not disappointed.
Stiles’ voice is equally tinged with something strange that makes him sound strained when he defends his manhood. “No way, Der. My dick is definitely bigger. I mean, I'm sure yours is perfect-” Stiles sounds wistful for a moment, and Cora can picture the goofy look on his face for a half a breath before he's scrambling to amend himself “-ly nice! Perfectly nice! But mine is like. Big, ok.”
Derek sounds just as surprised as the little noise Stiles lets out when Derek says “Prove it.” Cora has to bite her cheek to keep from groaning at the ridiculous cliche that is her brother and his best friend's denial-flirting. The relative silence of rustling clothes- holy crap, are they literally measuring their dicks right now?!- is broken when Derek gasps “Holy shit, Stiles. You're huge!” The awe in his voice has Cora burying her face in her hands to smother her laughter-her brother is having a sexual revelation on the other side of the door, and he still manages to sound like a total nerd about it.
When Stiles jumps in to defend Derek's dick, Cora is officially thisclose to hysterics; these boys are morons. “Hey man, yours is like, really nice, too. Thick and whatever, I bet you're a grower, too,” Stiles’ voice sounds deeper and his words are slow, much slower than his usual ramble. He says something too low for Cora to hear, but it’s sharp like a curse and makes Derek inhale sharply. Then he asks, hesitantly, “Can I,” and there's silence for a moment until they both moan, and Cora is struck with the awful realization that Stiles is currently giving her brother a handjob about ten feet away from her and all that is keeping her from having to actually witness the horror of that is an inch and a half of obviously way too thin plywood.
As she scrambles to her feet she hears a whimpered “The door,” and the unmistakable click of a lock turning. Before she can slam her hands over her ears and retreat to Laura's room to share the latest in the saga of his and Stiles’ tragic ineptitude, there's the equally unmistakable sound of sloppy, lip smacking kisses, a muffled “Oh god,” and “- so long…” and Cora has never regretted the fact that the second floor bathroom is on the other side of Derek's bedroom so much in her life. Not even that time she had the stomach flu and eventually just stayed a blanket into the bathroom with her to avoid having to run back and forth.
By the time she bursts into Laura's room, she's 99% sure they are having some kind of sex, because there's a faint knocking rhythm that is coming from the other end of the hallway, and it's all she can do to stage whisper as she recounts the last few disgusting moments to Laura. Laura who can't stop laughing into her pillow at the look on Cora’s face. Her siblings are the worst.
A particularly loud moan filters through the walls, and Laura stops laughing abruptly to pull a face and whisper through her amusement “Get it, baby bro!” She collapses back into hysterics a second later, and after the shock of it wears off, the next lewd sound pushes Cora over the edge and soon her and Laura's cackling almost covers the sound of Derek and Stiles fumbling toward losing their virginity.
As the door to Derek's bedroom closed behind them, Stiles felt the familiar mix of relief and anxiety that always accompanied time alone with his best friend. On one hand, it was awesome to not have to share Derek with anyone else, to not have to compete for his attention. Not that it was actually a contest, Derek never ignored him, or chose anyone else over Stiles in anything, but Stiles tried not to monopolize all Derek's time. Really, he did.
It just never worked. Every time Stiles stayed quiet too long, or tried to put physical distance between them (a necessity for his own sanity, sometimes) Derek would drag him back into the conversation with a “What do you think, Stiles,” or literally drag him closer with an arm around his shoulder, or a hand on the back of his neck. It was ridiculous. And endearing. And that, that is the reason for the anxiety.
Because Derek was his best friend, the best person Stiles knew, and Stiles was absolutely crazy in love with him. Derek had no idea what the casual touching and the constant, sincere attention and his stupid, beautiful smile where his little bunny teeth peeked out from under his lip did to Stiles. No idea how torturous and incredible it was to be the focus of that much affection from someone like Derek Hale.
And Stiles has no idea how to turn it off. How to stop being enamored with his best friend. How to stop the ache in his chest whenever the idea of Derek dating someone else crossed his mind. Earlier that day, Kate, Allison's aunt had come to pick Ally up after school and she had been all over Derek. Derek was clearly uncomfortable (Kate was a few years older, and had clearly never given subtlety much thought), and a little oblivious, but someday he'd stop being so clueless and flirt back with someone, and Stiles was terrified of that day. He didn't know how to be Stiles without being Derek's.
Maybe that's why he didn't have his usual self control, there had to be some explanation for why he started a conversation that could potentially lead to sex, let alone gay sex . Something Stiles avoided even thinking about around Derek for fear of revealing himself. But he was on edge, so as he settled himself on Derek's desk chair, carefully avoiding his bed, he found himself blurting out “So, who do you think tops? Danny, or his new boyfriend?” He isn't sure who looks more surprised, Derek or himself.
Derek was pretty sure today couldn't get any weirder. Stiles had been acting strange, sitting far away from Derek, keeping unusually quiet. He'd been doing that more and more lately, and Derek hated it.
He knew that the way he felt about his best friend was more than friendly, and that the need he had for the other boy to be close was probably a little possessive, but Stiles just made him happy. And this was usually his favorite thing; just him and Stiles, facing an afternoon of video games and enjoying each other's company, alone except for the occasional interrupting sibling.
Today though, Stiles was being weird. He was stiff and awkward when Derek would throw an arm over his shoulder, it only lasted a split second, but it was so unlike Stiles, it felt like ages. And when Allison's aunt had been talking to him that afternoon, touching him for uncomfortable seconds for reasons Derek didn't understand, Stiles had approached him almost cautiously, a weary crease to his brow that made Derek confused. He was always so attuned to Stiles, he had automatically looked up as he had walked toward him and Kate, and Derek had felt a flash of giddy relief that his best friend was there to rescue him from the older woman's strange attention.
But Stiles had had that face. Though, when Derek called to him and slung an arm over his shoulder he'd relaxed, it's reassurance didn't settle all the way through Derek, and he was worried that Stiles had figured his feelings out.
Still, there was the familiar relief of closing the bedroom door, of stealing Stiles away from the rest of the world and getting to bask in his attention.
Derek was wholly unprepared for the non sequitur about Danny and his new boyfriend. If he had been drinking, he's certain he'd have spit it everywhere, as it was, he practically choked on his own shock. “What,” he doesn't quite manage to make it a question, but Stiles answers anyway.
“Um, I just was thinking about- I mean, not that I think about Danny that way, I just,” Derek can barely hear what he's saying really, because the flush of pink that is painting Stiles’ face and neck is very distracting, and he wonders if Stiles’ skin feels warm where it's blushing. And he's always thought Stiles nervous rambles were kind odd adorable, and the loudest thing in the world in that moment is the thundering mantra of Don't think about sex and Stiles don't think about sex with Stiles don’t think about sex don't that is playing on a loop in Derek's head. That is, until Stiles says “I mean if it was us, then it'd be me on top obviously, but I'm not sure with Danny.”
Derek is positive he misheard, but even though he's now confronted with the idea of sex with Stiles and Stiles inside of him, and it's all in Stiles unexpectedly deep rumble of a voice, well, he can be forgiven when all he can manage is a squeaky “What,” that he meant to sound incredulous.
When Stiles answers, overly excited and cocky with “Dude, I'd totally be the top if we had sex,” Derek manages to get his brain back online enough to know he should redirect the conversation, but what comes out instead is an argumentative “No way, man. It'd definitely be me, I mean I know it's not how these things are decided, but my dick is bigger, so..,” his voice sounds strained, too high, the mental image of Stiles’ dick now replacing the anti-sex mantra in his mind wiping out any sort of control he has over his speech.
But he doesn’t have time to be embarrassed, because when Stiles responds, his voice is equally odd, and a little thrill runs through Derek at the possibility that Stiles is having the same troubles he is., because Stiles’ “No way, Der. My dick is definitely bigger. I mean, I'm sure yours is perfect-” sounds almost wistful, and his face is soft and dreamy for a half a breath before he scrambles to tack on a hasty “-ly nice! Perfectly nice! But mine is like. Big, ok.”
Derek takes a deep breath and swallows heavily before he attempts to speak again, and when what comes out of his mouth is a challenging “Prove it,” in a tone that no one could mistake for anything other than curious and hungry , he is just as surprised as Stiles, who lets out a small, startled sound. Their eyes are locked now, and Derek tries not to read anything into the hot look that Stiles is giving him. Stiles nods and drops his hands to his belt, gesturing with a tilt of his head and a quirked brow for Derek to follow suit.
For a moment, the room is silent save for the quiet rustle of denim and cotton, the soft clink of belt buckles hitting the floor, and the increasingly ragged breathing of two teenage boys about to be mostly naked with their best friend. When they both stand in t-shirts and boxer briefs, Stiles’ emblazoned with the bat signal, and Derek’s Superman’s symbol, a running gag between the two of them, they stand staring at each other for a long, taut moment with fingers hooked in their waistbands and their breaths coming fast and too loud in the stillness of the moment.
Stiles’ tongue darts out to wet his lips and Derek’s eyes trace the movement hungrily, he is pretty sure he manages to suppress the whimper that he feels trying to escape, but then Stiles pulls down his underwear and Derek’s mind is full of white noise and all he can do is gasp in awe, because “Holy shit, Stiles. You're huge!” And he really is. Stiles’ dick is long and heavy looking, a neatly trimmed patch of dark hair makes the pale, flushed skin stand out enticingly, and Derek has to fight the urge to drop to his knees and test its weight on his tongue.
Stiles blushes again, despite the pleased grin on his face, and then he looks at Derek’s crotch. Derek is more than a little shocked that he isn’t completely hard, but he figures nerves are to credit wit the fact that he isn’t completely embarrassing himself. Then Stiles’ breath catches slightly and he leans a little closer, almost imperceptible, but Derek is used to paying extra close attention to Stiles. Derek is wholly unprepared for the breathy and enthusiastic defense of his own dick that starts falling from his best friends plush mouth.
“Hey man, yours is like, really nice, too. Thick and whatever, I bet you're a grower, too,” Stiles’ voice is impossibly deeper and his words are slow, much slower than his usual ramble. He curses under his breath, a breathless “ Fuck me ” that makes Derek inhale sharply. When he asks hesitantly, “Can I,” his hand hovering in the small space between them- and when did they get so close ? Derek was certain that when they started they were practically on opposite sides of the room, but now there was barely an arm's length between them- Derek can only stare at his friend’s face, familiar except for the unmistakeable desire on it, stealing his breath. He can only nod, staring at Stiles’ slightly parted lips and licking his own.
As Stiles’ hand closes experimentally around Derek’s dick, they both moan in unison, and the sound of it fills the whole room. Stiles moves closer to him, turning so they face each other fully, his free hand settling uncertainty on Derek’s shoulder, and Derek can’t not lean into the gentle pressure of Stiles’ touch. There’s a low sound, and neither could tell you which one of them made it, but then Stiles’ long, slender fingers are sliding up and down Derek’s now painfully hard shaft, a slow, dry dragging sensation that is better than anything Derek’s ever managed on his own.
Derek manages enough coordination to cradle Stiles’ face, his thumb stroking along his perfectly formed cheekbones drawing Stiles’ eyes to his own and away from where he was watching his hand move along Derek’s dick with rapt fascination. After a few shared panting breaths, they just sort of fall into each other , lips meeting in a soft, experimental press. They don’t even manage to close their eyes, they have to settle for fluttered lashes and a shared sigh into the space between them before the kiss intensifies.
In the space of a single breath, Derek’s breath specifically, exhaled slow and sweet over Stiles’ lips, the atmosphere in the room shifts; Stiles hand tightens around Derek’s erection, his thumb swiping over the precome gathered at his tip and spreading it liberally over the flared head of Derek’s cock, his thumb sliding easily and teasing at Derek’s frenulum with just enough pressure to keep Derek on edge. While his ministrations are becoming more earnest, Derek is giving everything he has to the kiss. Stiles whimpers when the slick tip of Derek’s tongue glides slowly against the bow of his top lip, and then they’re kissing. It’s a dance of lips and tongues and teeth, slow and sensuous, lips catching and slipping against each other, tongues tasting in careful sweeps, Derek’s hands are buried in Stiles’ hair, and Stiles’ free arm is wrapped around Derek’s shoulders. Derek’s hips are shunting back and forth, fucking into the tunnel of Stiles’ hand.
Derek kisses his way along Stiles’ jaw and gasps into his ear, Stiles manages to squeak out “The door!” and Derek stumbles to click the lock as quick as he can, the sound like a thunderclap. Before Stiles can finish struggling out of his shirt, Derek is back in front of him, helping him free his arms from the tangle of his shirt sleeves and fitting their mouths together in a messy, desperate kiss, the slick, smacking sound obscenely loud and undeniably arousing. Derek’s hands are everywhere , running over Stiles’ skin reverently, fingertips bumping and gliding over his shoulder blades, his back, tentatively rubbing and kneading the globes of his ass, making Stiles moan around Derek’s tongue, throw his head back and whimper .
His hips move automatically, pushing his cock into the crease between Derek’s thigh and groin, and Derek groans out an “Oh, god,” that makes Stiles shiver. Derek buries his face in Stiles shoulder and sucks at the sensitive skin there, saying into his shoulder something that sounds like “I’ve wanted you for so long,” before gently pushing Stiles’ head to the side so he can continue to nuzzle into the space, leaving a trail of messy, perfect kisses along the pale, smooth column.
Stiles can’t quite make sense of that, but he latches on to it and replies honestly with “Me too, Der,” which apparently makes Derek really hot because because he practically growls into Stiles’ neck before tearing himself away to search Stiles’ face. He must find whatever answers he’s looking for, because in the next second he’s devouring Stiles mouth in the most devastatingly perfect kiss that Stiles could even imagine.
For a few moments, they’re just a mess of groping hands and desperately thrusting hips and perfect, messy kisses. Stiles is stroking Derek’s back, his chest, and scrambling to wrench his shirt off of him, but neither wants to break the kiss long enough to take it over his head. Stiles’ dick slides along Derek’s thigh and it’s slickness makes Derek groan and wrench away, his hands gripping Stiles’ upper arms tightly. He’s panting and his eyes are lust glazed and unfocused. Derek blinks for a long moment, their hips still flush and moving restlessly together. Derek drops one hand to Stiles’ cock, ends up holding them both together and running his hand up and down their joined shafts, moving easily through the precome slicking their lengths.
“Can I,” he asks thickly, darted a glance to where their dicks are pressed together in his hand and licking his lips. All Stiles can do is moan a broken sounding “Yes ” as he finally manages to wrestle Derek’s shirt off. He barely has a moment to appreciate the lightly muscled glory that is Derek Hale’s body before the boy is dropping to his knees and unceremoniously swallowing half of Stiles’ dick in one go.
It isn’t elegant, but the blissed out look on Derek’s face, and the absolutely filthy moan he lets out is enough that Stiles is pretty sure he could come just from this, just from Derek’s sloppy, wet bobbing on his dick, the not quite enough suction, and the look of pleasure on his face. Stiles’ knees feel like rubber, and his legs are shaking; his head is full of fizzy soda pop and his heart is jack rabbiting in time with Derek’s hands squeezing his ass. “Der,” he manages to breath out, and before he can finish his thought Derek is pulling off of him with a dirty pop and kissing him again. The trace of saltiness that Stiles knows is his precome probably shouldn't turn him in like it does, but it's intoxicating all the same.
Then, Derek is holding him close, crowding him slowly and deliberately back towards the bed, his hands careful and supportive even as they dig into the space between his shoulders and the swell of the top of his ass. Their progress must be too slow for Derek's liking, because Stiles finds himself hovering in the air for a second, only avoiding flailing and unbalancing them because his arms tighten around Derek’s neck and Derek uses the momentum from hoisting Stiles off the floor - something he'll have to remember to be indignant about later- to wrap Stiles’ legs around his waist.
And really, the way it traps their dicks between them, the way it brings their whole bodies into contact, the fact that Derek can lift him like that- it's all just so fucking arousing. And when Derek lowers Stiles into the bed and his weight settles over him, it's game over.
Despite the gentleness that Derek set Stiles on his bed with, the headboard makes a loud banging sounds against the wall, and some part of Derek knows that he should be being quieter, the ridiculousness of the headboard banging against the wall makes him laugh a little into Stiles mouth.
He pulls away to explain himself, but Stiles is already grinning, “Dude, the headboard! Priceless!” Derek should've known he'd get it, Stiles is his best friend, after all. They're kissing again before they stop laughing, kissing and crawling further up the bed. When they settle back down, heated skin pressed together from their joined lips too their tangled legs, the roll and grind of their lower halves is instinctual.
The kiss is still sweet and desperate all at once, Derek and Stiles taking turns licking into each other's mouths, nipping at plump, kiss swollen lips and sucking on each other's tongues. Their hands are still exploring, soft and clumsy and clinging in turn. They're practically fucking now, the slide and drag of their flush bodies creating a delicious friction on their spit and precome slicked cocks as Stiles raises his hips up to meet Derek's every downward thrust. The headboard slams into the wall every few times, and they smile against each other's mouths.
Stiles has one hand on Derek's ass, kneading and teasing a finger along his cleft just to feel Derek shudder against his chest and Derek is running a thumb in slow, feather light circles around one of Stiles’ nipples, and they aren't quite kissing anymore, just panting into each other, lips touching and occasionally dragging together wetly. Stiles gasps “So close,” into Derek's mouth and Derek pulls away to rest his forehead on Stiles shoulder and moan out “Yeah? Fuck ,” as he runs one big, strong hand up from Stiles’ hip to grab his thigh and hike it up high on his own hip, gaining leverage and increasing the pressure between them.
They grind against each other for a long moment, Derek cradling Stiles’ face in his other hand, his thumb tracing Stiles bottom lip, pulling it slightly. When Stiles curls his tongue around the digit and pulls it into his mouth, biting the pad gently and flicking his tongue over the sting in quick flutters, Derek's eyes roll back in his head and his hips stutter before resuming their rutting in earnest. When Stiles sucks Derek’s thumb into his mouth, eyes locked on Derek's the whole time, they both make an obscene sound and start moving together harder and faster.
Derek pulls his thumb out of Stiles’ mouth to reclaim it with his own and uses his wry thumb to tease and roll Stiles’ nipple, pinching the small pink nub until it's peaked and over sensitive, swallowing Stiles whines like a starving man. Stiles bites at Derek's lip, kisses along his jaw and neck, nipping at the straining tendons there. They're fucking against each other with abandon now, dicks slipping in a pool of precome, the pressure not quite enough, Stiles hips shunt upwards sharply when Derek curls over him to lick at a nipple, and it makes Derek's dick catch on Stiles’ rim; they both whimper, then freeze, staring dazedly at one another.
Derek pants out an apology, and Stiles assures him it's unnecessary with a smile and a kiss. “If we had supplies, I'd be begging for you inside me,” he murmurs into Derek's ear, fingers carding through his hair as Derek sets a slow careful rhythm to their rolling hips. Stiles doesn’t know what possessed him to say it, he’s never had more than his own fingers anywhere near his hole, and until earlier today he’d only ever kissed in the context of Spin the Bottle and Truth or Dare, so all encompassing was his crush on his best friend. It seems to snap something in Derek, because he's moaning and cursing and gripping Stiles tight, and then he's sitting up and holding their lengths together again, fucking into his hand and using his grip on Stiles’ hip to encourage him to do the same.
“I’ve never- never wanted anyone but you. But I want to. With you,” Derek struggles around his harsh breathing to get the words out, but it is the best thing Stiles has ever heard, so he kisses Derek to share the elation singing through him. Stiles adds his own hand, and a few messy, awkward kisses and hard, slick thrusts later, they're coming practically in unison; warm, sticky white striping both of their chests and dribbling over their now lax fingers.
It's very quiet, save for their labored breathing, and both have a moment of panic that it's about to be awkward. But then, there are lazy, sated smiles, and Derek drapes himself half over Stiles, careful not to put too much weight on him. Then, there's slow, drugging kisses that are mostly just fitting their lips together in varying configurations with intermittent swipes of tongues, they settle easily against each other, hands clasped and resting on Stiles chest while they play with each other's fingers.
By the time their breathing has evened out, they're pressing smiles into each other instead of kisses, and both half dozing. Suddenly, a shock of panic jolts Stiles from his post coital haze, “Shit, you don't think your sisters are home, do you? Cause we were not quiet, Derek!”
Derek freezes for a moment, considering the possibility that the house wasn't as empty as he'd assumed, that they've been overheard, that they'll have to deal with the merciless teasing his sisters will mete out. That they won't be able to decide to hide their-whatever this is going to be- from anyone. Then he looks at Stiles. At the wide blown pupils and the way he's biting his still swollen lips. Swollen from their kisses. And Derek smiles, kisses the worry off Stiles’ face and chuckles, shrugging as best he can while still curled around Stiles’ body.
“Eh, the door was shut. They can't have heard that much without trying to.” Stiles relaxes against him, and Derek feels his heart swell in satisfaction. His eyes slide to the locked door briefly before they close, perhaps he'll look into what it’ll take to get a thicker door tomorrow? Because being quiet isn't something he's terribly interested in.