Derek Hale walks through Beacon Hills on the day of the 178th annual Mating Ceremony. He passes by some of the town's other denizens, all of whom gossip amongst themselves and speculate who will be bound together for life the following morning. It's the same every year, ever since the ceremony was established to help the alphas of Beacon County find their mates.
Some see it as a chance to claim the objects of their desires, even though they have never explicitly made their intentions known before. Some look forward to finally making their existing relationships official. And then, even though Derek thinks they're crazy, there are those rare few who take part without a particular mate in mind, just for the thrill of it.
Derek himself falls in the first camp. For years now he has known who he'll pick when the time comes—Stiles Stilinski, an omega werefox.
Ever since Derek laid eyes on the boy and befriended him many years ago, he has known Stiles is his. Even though neither of them had presented yet, some instinct deep inside told him that they were meant to be. He kept it a secret from most people, and even now he thinks the only ones who know are his older sister, his parents and Stiles' dad.
Derek's sixteenth birthday came and went, he presented as an alpha as he knew he would, and still he didn't take part in any of the ceremonies. It wasn't time. Stiles was too young.
But that isn't the case this year. Derek's long wait is over. Now sixteen himself, Stiles finally has his second gender and is eligible to participate in the ceremony. It'll be his first, which means it will be Derek's first, too—and if he has his way, it will be the last for both of them.
Shaking himself from his thoughts, Derek continues on his way. He hasn't got much time left to get to the edge of the preserve, where the beginning of the ceremony is held. He knows that Stiles and his dad are already there, as are most of the others who will be running this year. The thought of any of those people laying eyes on what is his and wanting has him walking faster, his hands shoved in the pockets of his jeans as the wind whips around him, blowing through his short black hair.
He walks for five more minutes before the preserve comes into view.
There is a large crowd this year, unusually so, which sets Derek on edge. He pushes his way through the spectators, the family members and friends of those taking part, until he reaches the front and can join one half of the participants, the alphas.
He hears shocked murmurs behind him as some of the townspeople notice him and talk to their neighbours. Seeing him here after so many years of him skipping the ceremony must shock them. He is aware of what this town thinks of him, how he is regarded as an unpleasant hermit who has no interest at all in being mated to anyone. They don't know him, though, and the only person whose opinion matters to him is Stiles.
Speaking of the omega, out of the corner of his eye Derek spots him. He looks nervous, his enchanting cinnamon-coloured eyes scanning his peers anxiously every thirty seconds as if he is searching for someone. The mayor is talking to the two groups, but Derek doesn't hear them. All of his attention is glued to Stiles. The omega scans the crowd of alphas again and, when his eyes finally meet Derek's, the frown on his face is replaced by a relieved smile.
Obviously Derek wasn't the only one anticipating their impending mating.
The two keep looking at each other while the mayor continues with the rigamarole of explaining the ceremony, as if everyone present doesn't already know it inside and out. Derek ignores the mayor and takes in Stiles' state of dress—or undress. He is in just a pair of boxer-briefs, a smart choice that will make it easier to shift into his much smaller and more agile fox form. His pale, mole-dotted skin is slowly overtaken by the red flush of anticipation and arousal, the strongest lodestone Derek has ever encountered. It causes his gums to ache as his fangs try to break through, but he doesn't let them. Not yet, he tells himself.
Derek only breaks eye contact when the mayor's voice booms, "One…two…three!" at which point all of the omegas shoot off into the trees and he has no one to keep eye contact with. The alphas are left behind with the spectators, all of them antsy to give chase. Derek knew it would be like this. That is the whole point of the ceremony being set up this way, after all—to tap into an alpha's predatory instincts to hunt down their prey.
Well, if what they want is for him to hunt down his mate, then a hunt he'll give them.
The mayor keeps the alphas waiting for several tense minutes before finally counting down again.
Derek bends his knees slightly so that he can launch himself forward.
He blocks out everything but the mayor and the thought of his soon-to-be mate. The seconds tick on, and then, finally…
In a blur of motion, the alphas race after the omegas. Derek is near the back of the group as it splits apart, everybody going in different directions. When he is just inside the tree line, Derek stops temporarily to literally tear off his clothing, uncaring as fabric frays and seams split. It's all old anyway, chosen specifically because he knew he wouldn't be able to afford the time to strip properly.
When he is naked, Derek calls forth the beast within and allows his full shift to overcome him. It's fast thanks to years of practise, and then he stands on all fours, a huge wolf covered in dark fur, ready to hunt down the little red fox that is Stiles.
Knowing that he has already wasted enough time changing, Derek starts running again and breathes through his nose, searching for a hint of Stiles' scent. He knows it better than anyone else's, but it still takes longer than he would like to pick it out amongst all the other scents of omegas and alphas hanging in the air. Once he finally has it, he follows the trail.
The preserve is alive with sound as Derek runs, with growls and howls, yips and the patter of paws from those who have transformed like himself and Stiles. It's distracting, but he keeps his nose to the ground and just concentrates on not losing his omega's trail. He follows it for a long time—he has known how swift Stiles is in his fox form since they both learned to shift long ago, but somehow Derek is still surprised by how deep into the preserve Stiles has gone. The trail loops around itself, goes backward and forward, likely in an effort to prevent anyone else from being able to claim him.
It's probably also a game of sorts.
Stiles wouldn't be Stiles without some mischief, and Derek can just imagine the deviously happy expression on the fox's little face as he wove in and out of the trees. For a long time Derek tracks his omega, until the trail stops suddenly. He stands on the edge of a clearing and makes a questioning noise, staring down at the dirt where Stiles' tiny paw prints end. How is that possible?
Derek spins in a circle and sniffs the air again, trying to pick the trail back up, but he can't find it. For the first time that night he feels fear that some other alpha may beat him to Stiles. He can't let that happen. He is pacing around the clearing a little desperately when he hears something that makes him freeze. The sound is just barely audible, but it's there, high above him. Derek knows what it is—Stiles' vulpine laughter. This is a trick. Raising his head, Derek scans the trees in front of him a couple of times before he spots them, two pinpricks up in some low branches. They widen and then all of a sudden a flash of red comes right for Derek.
The werewolf doesn't have time to react before Stiles is jumping on his head and then darting off in the opposite direction.
You little brat, he thinks, amused despite himself.
Derek chases the fox before he can disappear from sight. As fun as it would be, he doesn't have the patience for games and just wants to claim his mate right then and there. His strides widen and he lowers his body closer to the ground to make himself more streamlined. He moves faster, to the point where even Stiles' agility shouldn't be enough to keep him from being caught.
They chase each other in between tree trunks and up and down steep hills, but every time Derek gets close enough to catch the white end of Stiles' ridiculously fluffy tail between his fangs, the fox seems to get a sudden burst of extra speed that puts him just out of reach. Derek growls irritatedly every time it happens, and by the fifth occurrence he wonders whether he will actually be able to catch Stiles after all.
He slows to a trot and then stops completely in the centre of another clearing, where he waits to see what Stiles will do when he realises he is no longer being chased. It takes a couple of minutes, and then light footsteps approach Derek's vicinity and he can just about see a red face peeking out through the green leaves of a bush in his periphery. Stiles' head tilts to the side in confusion, and he makes a noise as if he is asking Derek what is wrong, but Derek keeps his head turned away, hoping to be the one doing the tricking this time around.
His plan appears to work at first—Stiles leaves the concealment of the bush and steps closer to Derek, but then, just as Derek is about to whirl around and pin the fox in place with his front paws, he picks up the sound of someone else getting too close for comfort to the pair of them. He turns even further from Stiles instead of toward him, his hackles raised as another werewolf emerges from the darkness, ignoring Derek's defensive stance. They ignore Derek completely, their eyes locked on where Stiles stands a couple of feet behind him.
Derek bares his fangs, a warning to the other werewolf to back off, but they either don't notice or don't care. Either way, Derek doesn't like the possessive glint in their eyes, so he steps to the side to obscure their view of Stiles. This finally brings the other werewolf's attention onto him with a snarl that clearly says, "Get out of my way."
Their fur is a tawny colour and looks coarse, like it isn't well taken care of. They're a bit bigger than Derek is and their eyes are a darker red, but Derek doesn't allow himself to be intimidated.
He snarls back and braces himself for a fight, which he gets. In the next second, the other werewolf lunges for him and Derek retaliates by doing the same thing. They collide in midair and fall to the ground in a heap of growling and scratching. Derek howls when he feels a searing pain in his side where one of his adversary's claws nicks him. Instead of giving the other werewolf another opening to get an attack in, the pain only spurs Derek to fight harder.
He extricates himself and rolls away from the tawny wolf so suddenly that it leaves them bemused, clearly wondering where the black wolf beneath them has gone. This bemusement doesn't last long, but it's still long enough for Derek to gain the upper hand. He pounces again, and this time he manages to clamp his jaws around the back of the tawny wolf's neck. He is shaken around as they attempt to get free, but Derek just exerts more pressure on their neck until they are forced to go limp with a sharp whining sound, conceding defeat.
Derek tosses them aside and watches with angry satisfaction as they scarper off into the trees, tail between their legs.
The injury on his flank still throbs and probably will for a little while longer—he curses the slower healing rates of wounds from other alphas—but he blocks it out and turns his head in search of the reason he and the other werewolf had fought in the first place. Stiles lingers at the very edge of the clearing, mostly hidden again in the bush he had emerged from when Derek had stopped chasing him. Now that it's clear the violence is over, Stiles comes out once more and trots right up to Derek, giving up all pretences of the playful hunt he'd had them engaged in.
Knowing that his mate-to-be is safe, Derek sits on his haunches, catches his breath and holds himself still as Stiles leans in close to inspect his injury. He gives a small yip and then Derek feels his small, rough tongue tenderly sweeping across the cut. The werewolf winces but allows himself to be tended to.
For a few minutes Stiles cleans the wound, until the pain is gone and Derek stands up on all four legs again. The fox steps back around to his front and looks into Derek's bright-red eyes for a few moments, seeking reassurance that the larger were is alright. Derek bows his head and then, without further hesitation, Stiles presents him with the back of his neck.
Knowing what this means, Derek opens his maw and clamps his jaws around the fox's fragile neck. It's a show of trust that Derek would never even dream of abusing. A stark contrast to how he had treated the neck he'd just had in his mouth a few minutes previous, Derek is as gentle as can be as he picks Stiles up and begins carrying him away from the noise that can still be heard elsewhere in the preserve. He walks toward quiet, searching for one of the many caves that are scattered throughout the preserve for a singular purpose. They only see use once a year, on this very night.
Derek's hunt is over, and now it's time for him to make his claim official.
* * *
It doesn't take long for Derek to find a cave that isn't already occupied. The mouth is partially hidden by a moss-covered rock, which will provide ample cover while he and Stiles are inside. The cave goes deeper than Derek thought it would, which he approves of because it lessens the chance of someone else seeing Stiles in a state that only he should see him in. It contains a pile of blankets and an already burning campfire, which he knows was all put there by the townspeople who volunteer each year to deck out every known cave in the preserve in preparation for this night. Because the fire is already roaring, the cave is nice and toasty.
Derek puts Stiles down next to the pile of blankets and then takes the corner of one of them between his teeth to start rearranging them. He makes a nest of sorts, a large oval shape near the fire that will be perfect for their mating.
When he is finished, Derek turns around to locate Stiles and finds him stretched out beside the campfire. He is a long line of red and white fur and his eyes are closed in bliss as he enjoys the warmth of the flames. He looks as enticing as ever, and Derek doesn't think he can wait any longer. Eight years of pining was long enough, so he barks once to get Stiles' attention and steps purposefully into the nest, making it obvious what he wants to happen.
Luckily, the fox is as eager as he is, because he scrambles to his little paws and races over to the nest to join Derek. This close, Derek can already smell it, the slick that leaks from Stiles' virgin asshole. He inhales deeper than he has to to get more of that delicious scent, but it isn't enough. He has to have even more, so he circles around Stiles and knocks him over onto his side with a headbutt, an action that gets him an affronted yip. He ignores it and continues down Stiles' lithe form until he reaches his target.
Stiles' little hole is a sight to behold, wet and dripping and likely aching to be filled. It makes arousal flood Derek's entire being, his tapered cock already beginning to emerge from its sheath. He simply stares at Stiles' hole for a long time, until the way it clenches around nothing becomes too much to resist.
He hunkers down low to the ground and sticks his snout right in there, much to Stiles' surprise. The fox jolts but doesn't move otherwise, which is good because Derek honestly doesn't know what his possessive and predatory alpha instincts would've made him do if he had. The werewolf licks once, twice over Stiles' asshole. The taste of the omega's slick has his cock exposing itself fully to the air, his knot already throbbing at the base because it is desperate to be buried in his intended's tight orifice. That could never realistically happen while they are both in their animal forms—he would literally tear Stiles apart—but it's hot to think about nevertheless.
Derek continues his ministrations with enthusiasm, taking advantage of how strong his tongue is in this form to wiggle it past the tight ring of muscle and taste Stiles' insides. It's searing-hot, and he would happily fuck the fox's hole with his tongue for several minutes longer than he does, but Stiles grows restless. The omega shuffles away from the slick muscle invading his body and rolls over onto his back, all four of his legs in the air. It makes for a ridiculous sight, and Derek has a second to wonder what the hell Stiles is doing before most of his red-and-white fur recedes, his body grows larger and Derek has nearly six feet of gangly teenager lying supine in front of him.
The only parts of Stiles' fox form that remain are the tail between his legs, the two pointed ears that stick out of the hair on his head—adorable, Derek thinks—and his claws and fangs. The look in Stiles' eyes can only be described as sultry as he parts his legs and reaches between them to unceremoniously shove two fingers inside of himself. Derek stares with rapt attention, can't look away even if he wanted to.
"God, can't believe we're finally doing this," Stiles gasps out, inserting a third finger. "Thought about this every day since I presented."
Derek can relate.
"Fingered myself nearly every night thinking it was you, your fingers, your huge cock inside me instead."
When a fourth finger fits snugly inside Stiles' hole, the boy extracts all of them and holds his hand out for Derek to clean off. The wolf does so with alacrity and doesn't think he has ever tasted something as delicious as Stiles' slick. Once Stiles' hand has been cleaned and all Derek can taste is the fox's skin, Stiles grabs one of the blankets Derek hadn't used for their nest and shoves it beneath his lower back, raising his ass to a more convenient height. He parts his legs even wider and invites Derek to step between them, which he does.
"Hi there," the omega grins up at him.
Derek licks his face and then whines when Stiles' arms and legs wrap around him, holding him in place. The position puts his cock over the omega's balls, and he knows that if he moved just a little bit he would be able to sink into his hole. He doesn't try to, though, not yet. Instead he closes his eyes and begins to push back his inner wolf so that he can shift back to his human form as well, but he doesn't make it far. Stiles pokes him on the nose, distracting him from his task. He blinks open his eyes and peers down at the werefox, silently asking for an explanation.
"Not yet, Sourwolf," Stiles says, sounding a little breathless now. He brings his legs higher up Derek's body, which puts the wolf's cock right there.
Derek's eyes widen.
"Like this. Fuck me like this first," Stiles demands, his eyes flashing gold.
The werewolf is stunned. They may be weres, but never did he think that Stiles would want him like this. Then, after a moment of contemplation, he supposes that was stupid of him. After all, he finds Stiles' fox form attractive, so why wouldn't Stiles feel the same about his wolf form?
"Before you ask, yes, I'm positive," Stiles assures him. His face is flushed but he still wears a cheeky grin.
Derek doesn't need any more convincing; he'll take Stiles however he can get him, and if he is honest with himself, the idea of taking the fox like this taps into the most feral part of him and fills it with lust. With Stiles' limbs still wrapped around him, keeping their bodies pressed together, it isn't the easiest thing in the world to reposition himself so that he has the leverage needed to fuck the boy. But, after some careful finagling, he somehow manages it.
With the tip of his red lupine cock poised at Stiles' entrance, Derek can feel the heat of him and starts moving his hips forward, sinking in slowly because, even though Stiles is desperate for it and has already prepared himself, it's still their first time and Derek doesn't want to hurt him. When he is about an inch inside, the fox's hole clenches down on him repeatedly, like it is trying to suck him in further. Derek isn't one to deny Stiles anything, so he keeps moving until all eight inches of him are finally buried deep, right up to the knot. His furry balls rest over the top of Stiles' ass, so swollen and full of seed that Derek can't wait to pump into the guts of his mate-to-be.
Stiles' virginal walls are unbelievably tight around him, and his head is thrown back against the blankets as he gets used to being filled so completely. His fingers are knotted in Derek's fur, pulling it just hard enough to hurt, but Derek doesn't complain. While the omega adjusts, he just takes it and holds himself as still as he can, which isn't an easy feat. In fact, it's one of the most difficult things he has ever had to do, but it's worth it when the pained frown on Stiles' face is gone and he doesn't hold on to Derek's fur so tightly.
"Okay, Sourwolf," he says, his voice hoarse. "Fuck me."
Stiles' arms stay wrapped around Derek but his legs relax, keeping the alpha's upper body close but allowing his hindquarters more freedom. Derek takes advantage of this to withdraw from the amazing heat of Stiles' hole before plunging back inside, gradually picking up speed until he is fucking his mate hard enough that he pants with the effort it takes.
The sounds of their mating are obscene, the loud, wet squelches of Derek fucking his mate-to-be mingling with the moans of said mate. Derek mostly fucks into him with abandon, but he uses the Stiles' moans to guide him a bit so that he knows which angles will provide the fox with the most pleasure. Their faces are close enough together that each of his sharp exhales disturbs Stiles' hair and causes the pointed ears on his head to twitch—not that the fox cares. No, Stiles actually seems to like it, at least judging from the fact that his salacious and pleasure-filled expression doesn't change at all.
Derek knows his suspicions are correct when, after a particularly hard thrust that hits Stiles' prostate dead on, Stiles moves one of his hands, grabs the back of Derek's head and brings them even closer in a mess of a kiss. Derek closes his eyes and allows Stiles to do what he wants, to lick into his mouth and taste him. He would be worried about it being gross, but he had brushed his teeth before coming to the ceremony and he knows he still tastes mostly of toothpaste. Stiles seems to like it well enough anyway, because he doesn't stop licking at him.
After a while of this, Stiles switches tactics. He sucks Derek's rough tongue into his own mouth and then lets it hang open, an obvious sign that the alpha is supposed to take over. Derek gladly does so. He can taste toothpaste in Stiles' mouth, too, but beneath that is pure Stiles, an indescribable taste he knows he will never get enough of, no matter how much of it he has.
In truth, everything about Stiles is like that, even the parts of him that annoy Derek to no end. Their mating so far has already been amazing, far beyond anything that Derek had ever hoped for, but it's the thought of what will come afterward that tips it over into euphoria. His heart swells in his chest as what this night means hits him. He knew beforehand—of course he knew—but the reality of it, actually tangibly having it right in front of him, beneath him, around him, is something else entirely. Being inside of his precious omega and knowing with absolute certainty that they will be together for the rest of their lives, knowing that Stiles will be annoying him with his yammering about inane topics forever…it's perfection.
* * *
Stiles is also in heaven beneath the huge black wolf that is his mate. It's his place, where he was always destined to be, where he has longed to be ever since he was old enough to know what sex was and Derek entered his life. There are so many different sensations he is feeling all at once, and all of them are too amazing to even try to describe.
The cave is kept warm by the fire still burning a few feet from them, but most of the heat Stiles feels comes from the body atop his own. Werewolves radiate heat more than any other were, and Derek's wolf form is certainly no exception. It's almost too much, makes Stiles sweat, but he doesn't care.
He wouldn't change a thing about it.
The soft fur of Derek's belly rubs all over his front and the insides of his thighs with every jackrabbited thrust, stimulating his aching cock where it is trapped between them. The fur must be soaked in his pre-come by this point, he is leaking so much of the stuff, and from the burning in his gut that is only getting more intense every time Derek fills him up, it'll be soaked even further soon enough. Derek's fur is exquisitely soft, like silk beneath Stiles' hands as he clings to the wolf. He believes he could spend hours upon hours just running his fingers through it—maybe he will when they're done with their mating.
Derek's cock is unrelenting as it fucks into him, his hindquarters moving faster in this form than he could possibly move them as a human. Each time he withdraws until just the tapered tip is in Stiles, he is fucking back inside before the fox really has time to notice that he is gone. His cock is so thick and long that it reaches places deep inside that Stiles' own fingers could never hope to touch. It hits his prostate on every other thrust and makes stars explode behind his eyelids, the glide easy thanks to the slick he leaks in copious amounts to soak the sheets beneath them.
Derek's weighty, furred balls smack against Stiles' ass, sending little shockwaves up his spine, and he can feel the knot battering away against the rim of his hole, demanding entrance. He can't wait to welcome it inside when it finally comes time.
The lower half of Stiles' face is coated in slobber that drips down his neck, and his mouth is filled with Derek's tongue as they continue to sloppily make out. His own tongue grazes across the alpha's deadly fangs, giving the kiss a sense of danger that does nothing but heighten the pleasure he experiences.
Eventually, though, he has to bring the kiss to an end or risk suffocating. He tears his mouth away from Derek's and tilts his head to the side to take in huge lungfuls of oxygen. This new position puts his neck on display, something Derek takes immediate advantage of. Instead of plundering Stiles' mouth, the wolf licks across the expanse of vulnerable flesh and—with care and precision that Stiles didn't think he'd be capable of with how hard he continues to fuck him—takes small sections between his fangs to nibble on.
Stiles' skin isn't pierced even once, but he knows that by the time Derek is done, his neck will probably just be one big bruise. This image has him moaning and tipping his head back even further, pushing up into Derek's mouth because he wants to wear his marks more than anything. He wants everyone to be able to see evidence that he belongs solely to Derek, an instinct that he thinks has been heightened for both of them by the near-miss of him almost being claimed by someone else earlier that night.
The memory of how terrified he had been when the other werewolf showed up in the clearing has Stiles holding on tighter to Derek. He curls his tail up to entwine with the alpha's and babbles nonsense without thinking about it—words about how amazing Derek is; how glad Stiles is to have him as his mate; how much he loves him and can't wait to bear his pups.
The last sentence spurs Derek on, has him changing things up. Instead of the indescribably quick thrusts he was blessing Stiles with before, he slows down and makes each one more purposeful. Every couple of times he sinks in to the knot, he lingers and grinds it against the resistance of Stiles' hole, gradually coaxing it to relax and let the thickest part of him inside. Stiles relaxes his lower body as much as he can, knowing that it will be easier to take the massive bulb of red flesh that way, but it isn't easy. He can't concentrate on anything else and the anticipation has him tensing up involuntarily, not in an effort to keep Derek out but because he knows that this will be the culmination of their mating and they'll have to stop after this.
At least for a little while.
As enticing as the thought of being filled with Derek's seed is, Stiles doesn't want it to end just yet. He doesn't ever want it to end, but there isn't an effective way to communicate this because the ability to speak seems to have suddenly deserted him.
Every time Derek grinds his knot against Stiles' hole, the fox can feel himself opening up more and more, wider than he ever thought he could go. Although his mind is telling his body, "No, not yet!" his body doesn't listen. His hole sucks on the knot each time it comes close to sliding past, trying to get it in entirely so that it can seal tight as a vice on the other side, locking them together. It's odd to have such little control of his own body, but Stiles isn't afraid. He knows this is his biology, that he was quite literally designed to take what Derek is attempting to give him.
Maybe not the very-much-proportional cock of a massive werewolf in their alpha form, but a cock and knot all the same.
Stiles whines and moans and gasps nearly constantly, the sounds pouring uninhibited from his lips. He just keeps clinging to Derek and decides to stop overthinking it, to let it happen. His hole continues to open up under the alpha's onslaught until, finally, it stretches wide enough for the knot to shove past and up into Stiles' insides.
For a few seconds Derek becomes even more frantic in his movements, fucking the omega with his knot. It slips in and out several times, and every time he is left empty fills Stiles with distress and has him clenching around the thickness of Derek's shaft in an effort to keep himself full.
It seems to take Derek some time to come back to himself, to realise how what he is doing is affecting Stiles and put a stop to it. With one last thrust Derek sinks home and allows Stiles' asshole to clamp around the base of his cock, right next to the soft, fine fur of his sheath. They lock together, and Stiles sobs into Derek's neck as he spurts between them, the constant pressure of the wolf's knot against his prostate tipping him over the edge.
He has never had an orgasm like this before. It seems to last forever, and by the time it's over their stomachs are drenched in his come. But still Derek's knot is there, unremittingly stimulating him nearly to the point of pain. Stiles almost blacks out, it's so much, and he thinks he actually does for a few seconds when Derek starts moving again. Even though his knot is in, the alpha hasn't had his own orgasm yet and so he resumes fucking Stiles as much as he is able—which isn't much. He can only move about an inch or so without the knot tugging too hard on Stiles' hole, but it's enough.
By the time Stiles is coherent and can focus on what's going on, Derek is howling so loudly it nearly deafens him and then a bright pain spreads from the right side of his neck to the rest of his body. He knows that the werewolf has just buried his fangs in his flesh, breaking the skin this time in order to leave a claiming bite that will officially and irrevocably connect them together for the rest of their lives.
For a few seconds all Stiles feels is the pain of the bite, but then his mind and heart are occupied by something else—or someone else.
Realisation isn't instantaneous, not with everything he is feeling, but eventually he recognises the unfamiliar presence for what it is. Derek. He can quite literally feel Derek in his chest, a pulsing warmth that soothes the pain of the bite on his shoulder. Stiles blinks open eyes he hadn't realised he had closed and stares up at the ceiling of the cave as he parses through the new emotions that aren't his own.
He picks out the sexual aspects of it first, which makes sense given the positions that both he and Derek are still in. It's not exactly like he can feel everything that Derek is feeling, but there is some sort of phantom pressure around his cock that he knows is how his ass is for Derek. He wonders if Derek can feel something similar, if he is experiencing the phantom sensation of being filled so completely like Stiles is for real. He makes a mental note to ask him later on.
Once Stiles moves past that, it's like he can touch the very core of who the alpha is, everything that makes him Derek Hale.
There is both affection and annoyance for various members of his family.
There is fear that he isn't good enough, a sense of inadequacy that Stiles had never known Derek possessed.
And then—the thing that would knock Stiles off of his feet were he not already lying down—there is love.
It was a fact that Derek and Stiles loved each other. Everyone that has ever been around them when they are together is aware of this—it's concrete fact—but Stiles had failed to recognise just how deep Derek's love for him goes.
It's endless. Stiles doesn't think there is anything anyone could do to change it. Overwhelmed, he doesn't register the salty moisture trailing down the sides of his face until he hears Derek whine worriedly at him. He lifts his head and tries to meet the werewolf's eyes, but his vision is blurry from tears he can't prevent from falling.
"I'm okay," he croaks, laughing wetly. "It's just a lot, y'know?"
Stiles doesn't have to guess that Derek does know. The alpha's eyes are still burning red, but that isn't what makes them appear so warm. Stiles is certain that Derek is feeling everything he is feeling, that Derek can see deep into him and experience the wealth of emotion he feels for the wolf in return.
"God, I didn't think it would be like this," the omega says, his cheeks aching with how wide he is smiling. "No one warned me."
Stiles takes a shuddering breath and attempts to get ahold of himself—not an easy task, but he manages it and checks in with the rest of his body.
His cock is sore between them, and he frowns when he thinks he can feel even more wetness there than before, like he came a second time and just doesn't remember it. It's possible, he supposes, given how he had blacked out. Elsewhere, his shoulder twinges every time he moves even a little bit, causing him to wince. Derek doesn't miss this and is smart enough to know the reason why without having to ask. He licks across the bite, and something in his saliva dulls the pain. It will take a few days to heal completely—the healing rate of a werefox is slower than a werewolf's, especially when the wound is from an alpha—but Stiles believes he can manage until then.
His stomach is heavy. He frees his right hand from the fur on the side of Derek's neck, wedges it between them to prod at his stomach and discovers that it is distended ever so slightly. What's responsible is obvious, as Derek's cock continues to twitch and jerk inside Stiles' ass, pumping him even fuller with come. It's an oddly pleasant sensation.
Everything else about his body appears fine, just small cramps in his legs from having them bent up for so long that are easily remedied by some careful rearranging.
When that is done and his cursory examination is complete, Stiles sags back into the sheets and settles in to wait for Derek's knot to go down. He strokes his fingers through the wolf's fur like he'd thought he would earlier and just revels in the afterglow. He is comfortably warm now that his blood isn't racing so fast. The cave is suffused with the scent of their sex, a heady, musky thing that, if he hadn't already come two times in such quick succession, Stiles is certain would lead to him becoming aroused again.
He pokes at the new bond between him and Derek, testing its limitations and giggling when Derek pauses where he still cleans the bite on Stiles' shoulder and pokes him back. It's playful, and Stiles can't resist doing it again just to get another reaction from his mate. Derek lifts his head and growls down at him, a sound that Stiles doesn't find threatening at all. If anything it's endearing, and he just can't resist pressing a chaste kiss to Derek's wet nose.
"Love you, Sourwolf," he says, scratching behind the alpha's ears.
Derek pushes into the touch and rumbles, pleased, his tail disentangling from Stiles' and wagging back and forth across the ground.
Even though Derek can't say it back in this form, the glow in Stiles' chest gets brighter and he knows the sentiment is returned wholeheartedly. He can't stop smiling.
He doesn't think he'll ever stop.
Tomorrow there will be a bunch of stuff to do. They'll have to go to City Hall to register themselves as mates. They'll have endure the teasing of their families—Stiles can just imagine how red Derek's face will be when Laura and Cora get to him—and they'll have to figure out living arrangements. Now that he and Derek are mated, there is no way they can live apart like they currently do. Maybe Stiles will move in with Derek, or maybe Derek will move in with the Stilinskis until Stiles is eighteen.
The latter is the most likely option, but Stiles doesn't care—they'll figure it out, and as long as they're together, that's all that matters.
For now, Stiles stays in the blissful bubble he and Derek have created for themselves inside of the cave.
He keeps smiling.