Chapter Text
It’s so easy, so fucking easy to win the bet. And it’s not like Derek planned it, doesn’t even realize what he can do with 24 hours of Stiles having to do everything Derek tells him. It’s not before they’re alone, after the rest of the pack left on Derek’s orders, that he realize that he can use Stiles however he wants.
Stiles is staring at him, waiting for Derek to do something. There’s something in the air he can smell, like Stiles is thinking the same thing as him and his body is reacting. So Derek nods towards his bedroom and Stiles pads after him. Derek makes a last check before he closes the door, makes sure that the pack has left and that Peter isn’t lurking around somewhere, you never know with his uncle.
“So what now, I’m not supposed to clean your room am I? Really Derek, I don’t want to go through your dirty laundry.”
Derek has his back towards him, but he can guess how Stiles face looks like. The wrinkled nose and put off expression. He doesn’t really understand it, his room is clean and that’s more than you can say about Stiles, which always smells of sweat and dirt and slightly like cheese. It’s kind of disgusting.
“You’re here because you couldn’t keep quiet, so this time we’ll use this,” he says as he turns around, Stiles eyes grow wide, the cocky grin disappears.
He quickly hides behind another, but missing cocky because the nervous twinkle in his eye, “ Do you just have those kind of things lying around in your wardrobe.”
“Stiles come here,” he quirks his finger, and Stiles takes the last step towards him.
“Open wide,” he smirks, and Stiles glares at him but does as he says.
With Stiles mouth open he carefully arranges the spider gag into it, making sure that it stays comfortable behind his teeth. He also makes sure that the ring is big enough for him because yes, Derek is going to use those lips before the 24 hours is done. He sticks his thumb into Stiles mouth, just to feel the slick heat and pushes Stiles tongue down.
He can smell Stiles growing arousal. The other hand he runs up Stiles flank, drawing him in and Stiles keens behind the gag, turning red at the sound.
“Turn around,” he swirls his finger, just for the effect, watches Stiles awkwardly turn around, leaving his neck and back exposed to Derek. “Bend over. There just like that, chest on the bed, good boy.”
Stiles whimper again, fuck this is perfect.
He slowly disposes of Stiles clothes, starting with his shirt, tweaking one of his nipples just to hear him yelp, slightly garbled behind the gag.
Then he drags his pants off together with his underwear, exposing his hole to Derek. He runs a dry finger over the puckered skin, making Stiles jolt and moan. Derek grins slow and filthy grin before taking a step back.
“Just like that baby, now don’t move, I’m just going to get some things.”
From his wardrobe Derek gets some leather straps, lube, a cockring that he slips into his pockets and a butt plug, large and made of glass. Because he wants to keep his come inside Stiles as long as possible, and if he’s going to use his mouth too then… well.
When he turns around he has to stop, Stiles his bent over the bed, chest against the sheets and legs jittering, like he’s not sure if he should kneel or keep standing up. It’s, fuck, it’s obscene, if Derek didn’t have other things in mind he wouldn’t be too against leaving Stiles like this, making him wait for Derek.
But not now, instead he puts down the lube and the plug on the floor beside Stiles before tapping his shoulder.
“Arms, behind your back.”
Stiles turns to look at him, the angle a little awkward, but when Derek lifts his eyebrow Stiles reaches behind himself so that Derek can take his hands and bind them together, two leather straps with his hands at his elbows, making him push out his chest.
He uses the next straps to bind him against the bedpost, making it almost impossible for him to move; keeping him still and like Derek wants him. Open and gaping for him, not being able to do something. The last he puts on Stiles ankles, keeping him standing against the bed.
Next he takes the lube bottle and globs it onto his fingers, It’s cold and he should wait, but he doesn’t have to, it’s his decision to make so he shrugs and runs the now slippery fingers over Stiles crack, making him yelp against the gag and jerk forward, the straps doesn’t budge, just giving him a small leeway to move.
“Do you like it Stiles, me taking control, having you just like I want to, me using you,” he slips his fingers down, down, playing with Stiles balls and Stiles reacts so perfectly, shivering when Derek gets his hands on him, his cock filling out curling against his stomach.
He only slips the tip of his finger inside first, circling the hole slowly before pushing the whole finger inside. Then he’s working the lube inside, pulling out and pushing in, until he can stick another finger inside together with the first one.
“Your doing so good Stiles, doing so good for me,” he says when Stiles writhes on his fingers.
He squirts more lube into Stiles’ crack before working in the third finger. Stiles cock is dripping pre-come on the bed, him gasping as Derek cruelly wrings his fingers around. Derek’s dick is rubbing uncomfortable against the zipper on his jeans, having fattened already on Stiles first cry.
More pre-come drips from Stiles cock. Derek cocks his head to listen, Stiles’ heart is beating faster, breath coming out irregular from his mouth in short gasps.
“Do you want to come Stiles?” he asks.
Stiles gives him a halfhearted moan.
“Nod if you want to come, you have to answer me, do you want to come now, with only my fingers spreading you, I haven’t even worked this tight hole for my cock yet.”
Stiles gives a frantic nods, bobbing his head up and down, his eyes clenched shut. It’s then Derek slips the cock ring on him, he shouts out, probably being interrupted on the edge of his orgasm if Derek was reading the signs right.
Stiles turn again, glaring at him over his shoulders, but with the gag he can’t actually say anything to Derek. The angry look doesn’t work so his faces soften, giving a pleading little whimper. If it was any other time Derek would fall for it, but this is his, right now Stiles is his, which means he decides when he gets to come.
“Aren’t you a little slut, trying to come before I’m even inside you. You don’t get to come yet, not before I have come…” he hums, thinks it over a little, kneading Stiles ass with the hand not working his hole loose and sloppy, “four times.”
Stiles eyes widens, and its probably because he wants to come, Derek can see how obscenely Stiles cock is still dripping even with the cockring around him.
“Yes, four time then you get to come, and then we will see if we can work you up for another again after that, it doesn’t matter, I can work you over all night, and day, 24 hours really.”
He pulls out his fingers and then pushes his index fingers inside, then his middle fingers, stretching Stiles’ rim wide for Derek. “Did you know that, that werewolves can go on fucking a whole day, probably more than that. And when we’re done here, you’re going to be so full, after I have pumped you full, dripping come from your hole, smelling like my bitch.”
Stiles flush red in humiliation.
“Shh, don’t be like that, because you are, you are my bitch, my pretty little slut to do what I want with.”
He pulls his fingers out and gives Stiles rear a slap, making him whine.
There’s so much lube inside Stiles now that it’s dripping down his legs, his hole already looks sloppy and raw, and if this is just from fingering Stiles than this is going to be so much better than he thought.
He pulls down his zipper, thinking over if he should take of his clothes, but he likes it. Stiles being vulnerable and naked under him. Derek wants to see how Stiles ass while look after his jeans has chafed it red. Besides Derek still has time, he can fuck him now with his clothes on and then without.
“Are you ready to take my dick Stiles, ready to be worked over by my big fat cock?” he roughly parts Stiles ass, his hole gaping and twitching, like an invite for Derek to take.
He’s still big though, so he has to push, Stiles whimpers and tries to relax, not to clench down before the head pops inside. Then the whimpers turns to moans, drool dripping down Stiles’ chin and eyes growing misty as Derek keeps pushing, sometimes drawing back only to push in again until he’s fully bottomed out.
“You little slut, how are you still so tight,” he gives a tentative thrust, earning him another moan from Stiles. Stiles is breathing hard, in through his nose and out through his mouth. His breath gets caught in his lungs when Derek gives another thrust. He shakes when Derek pulls out even further.
“Hush baby, this is mine, your hole is mine, your body is mine, yeah, fucking slut letting yourself be used like this.”
Stiles blinks, and Derek fucks into him again. It’s fair play now, he grabs on cheek holding it open for his cock to pound into Stiles, his ass already turning red and irritated from the jeans rubbing against his naked back. The other hand snakes around Stiles chest, lifting him up as best he can with his body still tied down.
“Do you like it, being used, being a fucking cumslut for me, you do don’t you,” he smacks Stiles ass again, pawing at it roughly, “Nothing but another fuckhole, moan for me, just like that, so good…”
The best is the sound Stiles makes when he lowers his mouth to his neck, Stiles is smart, he must now what it means when a werewolf bites someone’s neck, and he writhes and keens so perfectly when Derek sucks and bites and licks hickeys on his nape, shoulders and back. Stiles’ cock is twitching and red, the cockring still making it impossible for him to come.
Derek’s orgasm is building up, a pull in his lower stomach. He raises his upper body up, and works his cock in sharp thrusts, rubbing the stiff fabric of his jeans up and down Stiles ass. His come paints Stiles hot inside when he finally comes hard.
“Good boy, making me come, this is the first. Three more” he murmurs into Stiles nape, kisses every mark he’s put there.
He waits until he’s cock is growing hard again, before starting to roll his hips. He holds his knot in, that’s only for the last time, when he can stay inside Stiles however long he wants. Stiles gives a twitch, seemingly surprised that Derek already is going again, even though Derek told him that.
“Clench down Stiles,” Stiles narrows his eyes at him, slurping on the gag like he wants to say something.
“Clench down around my cock Stiles or you’re not coming at all. I can do that Stiles, I don’t have to let you come, so be a good little bitch for me and work that hole for me.”
He groans when Stiles finally listens to him, the slick heat growing thicker around his cock, “good baby, being so good for me, doing what you’re being told to do.”
He rolls his hips, going slow this time, drawing out every moan and whimper from Stiles. Then he angles his hips just so, and Stiles screams his cock pulsing against the cockring.
This time the orgasm comes a little slower, gets drawn out from Derek, comfortable and slow, while Stiles his starting to go erratic, body twitching, hole clenching around Derek even as he starts to pull out, reaching for the plug on the floor.
“That’s two, half way there.”
He pushes the come that has been dripping out back inside Stiles with his thumb, before pushing in the plug. It fits inside the hole, stretching it wide for Derek, and he has to groan. It’s too good.
He undresses, the jeans have become sticky from sweat, but looking at Stiles he knows it was worth it. His hole already looks swollen and sore, red skin spreading around his ass, which is still clenching and unclenching around plug, Stiles still working his ass for Derek.
He climbs higher onto the bed know, grabs Stiles head. Stiles eyes finds him and he gives him a smile, sharp and proprietary.
“I’m going to use your mouth now baby, and you don’t have to do anything, but this hole is also mine,” he tightens his fingers around Stiles chin, tilting it upwards before slipping inside, he doesn’t have to be so worried about holding back his knot this time. The steel ring holding Stiles mouth open prevents him from forming one either way.
“You don’t have to swallow, I want to see my come dripping from your mouth.”
Stiles mouth his hot, and slick, more so than his other hole, and those plush lips wrapped around his cock feels amazing. He doesn’t go slow, pushing against Stiles throat until he hears him choking, and when he finally pushes inside and holds there, Stiles eyes begins to tear.
“Such a little cock whore, aren’t you,” he reaches the plug, moving it in slow circles before pulling at it Stiles rim squeezing it. Stiles jerks forward onto Derek’s cock, “I’m right aren’t I, so greedy for my cock, wanting to be filled from both ends. Or do you want to come.”
He rubs his foot over stiles cock, making him gag around him.
Stiles eyes turns pleading, so Derek has mercy on him and grabs his face, holding him still as he skullfucks him, hard and relentless before coming down his throat. He pulls out and watches Stiles hack up the come he can’t swallow, it drips down his chin together with the drool that the gag creates.
Derek smiles, “one more time.”