Archive of Our Own

If there is one thing you can count on about Buck in heat, it is that he needs to be filled.

Before Eddie, he made do. Fingers— index, middle, ring, and pinky— notched inside him until he was slick-soaked down to his wrist. Dildos of all shapes and sizes, some with knots and ridges, others smooth and long. Plugs, fat like a fist, smooth metal or firm silicon, locked inside his rim for the moments between waves. In his most desperate days, heat-ridden in the back of a jeep in his twenties, it would be anything he could shove inside him. Bottles and bundles of pens, and in one particularly brutal wave of heat, the gear stick of his car. He didn't care what it was, so long as it took off the burning edge of the heat spiking through his system. He didn't care as long as he was full.

When Eddie stepped into his nest, finally crossing the line of friendship, circling the word mate like an orbital, gravitational thing, everything changed. Because with Eddie came hands with fingers longer than his, thicker, better angled, and relentless, where Buck's might have fallen to uselessness in the throes of an orgasm. With Eddie came a cock, and with that cock came a knot, both blood hot and massive and so fucking filling. Bigger than anything he'd ever had, anything he'd ever dreamed of, filling him and then swelling in him like Buck was a thing to be forged to their shape. And with Eddie's cock—

mmm,

With Eddie's cock came his cum. Buck had never had anyone come in him before Eddie. Buck had never even wanted someone to breed him like that before Eddie. But fuck, if he was not filled. Eddie always comes like it's a full-body thing, like every one of his nerves and muscles and cells has no choice but to get lost in the pleasure, collapsing onto Buck as his dick throbs, and throbs, and throbs inside of Buck. An endless stream of cum, trapped by the knot inside him, flooding his goddamn insides until his stomach nearly aches with the pressure of it all.

It's obscene. Ridiculous. Eddie didn't even realize he could come like that before Buck, his alpha instinctively reacting to something about Buck, working over time to fucking breed him, with no regard to anything else his body might need that liquid for. They had prepped for that first heat, bottles and bottles of electrolyte water, and they had both still ended up dehydrated enough to take an extra day or two off work. They had laughed about it, breathless and disbelieving. And then Eddie had fucked him through the mattress about it, filling him even more, dehydration be damned.

And Buck… loved it. Fuck, he loved it. The pressure in his guts, the way Eddie could fill him in a way that nothing else ever could, plugging him and keeping the cum trapped between rounds, until he was cramping with how full he was, how full he was of Eddie, and still begging, voice cracking, 'please alpha, please, please, m-more, I need— need your knot,' as his hands cradled the taut bulge of his stomach.

And Eddie, because he was perfect—Buck's perfect friend, and perfect partner, and perfect mate— would always give in. Would give him another load, another knot, even when they were both sweaty and filthy and hungry. Would let Buck sleep and still knot him so the burning pleasure wouldn't wake him up. Would leave himself bare as he slept so Buck could still ride his cock, or turn them both on their sides and rock his ass back against Eddie until he knotted, even unconscious. He couldn't say no to Buck in heat, couldn't say no to how needy he was.

And that… well. Buck wouldn't exactly say that was the problem. But it was sure as shit what led to their morning predicament.

Eddie drifts into wakefulness in almost the exact same way he had fallen asleep. Three things are the same, at least. He's sinfully warm, he's surrounded by Buck's heat-adled scent of salt and peaches and cinnamon, and his cock is throbbingly hard between his thighs.

Unlike when he fell asleep, though, Buck isn't actively on his cock. Not riding it at least. He is fairly certain he can feel at least a few fingers and a tongue, though, massaging his half-popped knot and licking around the length of his shaft with the kind of attentiveness one normally saves for eating brownie batter from a spoon, like they can't spare a single missed spot.

The tongue travels to the head of his cock, digging into his slit, and a flash of heat coils in his gut, the first of many for the day. Eddie flutters his lashes open and stretches out languidly along the sheets, toes pointing and shoulders rolling against the mattress as he moans out a warm, drowsy, "Mmm, hell of a way up, Buckley. Thought I was the one who was supposed to be spoilin' you."

He tilts his head up from the mattress, staring down the line of his own body with half-lidded eyes, to where Buck is lying half across his legs, entirely naked and glistening with sweat, humping along the mattress in near sync with the drags of his tongue along Eddie's dick. His dick, which is, to his mild surprise, still somewhat coated in a filthy mix of omega slick and his own come, mostly lapped up but still matted into the hair around the base of his cock. Busy night, it seems.

As Eddie finishes talking, Buck pulls his mouth away from his cock, a filthy string of cum-slick-saliva dragging between the glans and his lips until it breaks after a few inches of distance, painting messily down Buck's chin. His lips are flushed red, a little puffy with the attention he had been giving Eddie's cock, and his eyes are blown massively dilated, tiny rings of blue around black holes fixing onto his face. And Eddie finds, for not the first or fifth or fiftieth time, and not certainly not the last, his breath taken away. Stolen from lungs with the sight of just how much desire Buck can fit into his expression when he looks at Eddie. Desire and hunger and love.

"Eddie," Buck breathes, like the word is a miracle, "You're awake."

The omega's hands squeeze once around his knot again, working it like a toy. It sends a wave of heat stirring in his groin, sends his teeth into his lower lip to stifle the muffled little "Nn," that wants to run past his vocal cords.

Eddie rides out the wave of pleasure, getting his shit together enough to reply, "Yeah, baby, woke up for you. Couldn't let you have all the fun by yourself."

Buck grins, a tiny little twist of his lips, and his scent perfumes into the air around them, a fresh wave of pheromones. "Had two waves of fun by myself, but I missed you the whole time." He grinds his hips into the mattress, and his face flickers a tiny bit with the pleasure, "Mm, I swear you're bigger when you're awake. And your cock, weirdly, doesn't talk me through it all by itself."

Eddie laughs, a tiny huff of air that simultaneously feels like all his lungs have to give. "That so?"

"Mmhmm," Buck draws out, hands squeezing again around Eddie. "Still get to hear all your little noises though. Love your moans. 'Nd I like to stick my fingers in your mouth sometimes, feel the vibrations of it up my bones while I ride you. 'S like haptic feedback."

"You finger yourself first? Is that why my mouth tastes like ass?" Eddie teases.

Buck smirks at him, little needle-like omega fangs flashing in the light of the room. "Big talk from someone whose dick is in biting range." He leans closer, raking his teeth once across the skin of Eddie's inner thigh, leaving little, dragging red lines. "You're lucky you need this thing to fuck me. Can't damage the goods."

Eddie's dick jumps at that, throbbing in the air between them, and Buck groans audibly, fangs digging a bit deeper into Eddie's leg. "Fuckkk," he groans into the meat of Eddie's thigh. "D'yknow that you react like that sometimes even when you're out 'nd I'm talk to you?"

"It's cause I'm dreaming of you."

"Uh huh?" Buck asks, breathless, giving a parting lick to Eddie's cock as he leans all the way up.

"All night long," Eddie promises. "Can't do anything but dream of you when you're touching me like that. When the whole nest smells this fucking good. When I have your taste lingering in my mouth."

"Thought you said it tastes like ass?"

"Never said that was a bad thing," Eddie replies, propping himself a little further up against the headboard. "I love eating you out. Love your slick. Love tasting my cum leaking out of you."

And Eddie knows exactly what he's doing, knows exactly what to say to tip Buck over from the clarity of an orgasm into the haze of another heat wave, and it works like clockwork.

Buck breathes out an airy little "Eddie," and his eyes go cloudy in the way they always do when he succumbs to heat. He shuffles and starts crawling up the mattress, eyes fixed on Eddie's dick, goal painted clear across his face. He straddles Eddie's legs, scooting up his body until he's sat on his thighs, hands leaning forward to brace on Eddie's stomach, and—

And—

(Eddie's had these moments in life, of delayed awareness.

He doesn't really know if it's a human thing or an Eddie thing, but he can go for surprisingly long periods of time not realizing something about his body. Entire lengths of days, not fully aware he hasn't eaten or drunk anything until he steps into the kitchen, and his body goes 'hm, you're missing something, actually.' Six hours of direct sunlight working a scene, where he doesn't realize he's long passed the line of hot and into heat stress until he steps into the shade and sits down.

On one memorable occasion, he went to check the mail barefoot, unlocking the mailbox and flipping through bills, and letters, and magazines with a languid, unrushed sort of ease, and only realized he had been planted nearly ankle deep in an ant hill when he glanced down and saw fire ants swarming up to his knees.

It's easy for him to miss a need until he's directly confronted with it. Hunger, or thirst, or exhaustion, or pain, or—)

Buck's hands press down on Eddie's stomach, and he becomes aware all at once, with a desperate sort of mental pinging, that the pressure and heat coiling in his guts was not arousal. Or at least not exclusively. It was an entirely different type of pressure, the type that has him reflexively tightening the muscles of his abdomen as Buck absentmindedly presses down against him as he shuffles forward, directly over his fucking bladder.

"Uh, Buck—" he groans out, back arching slightly off the bed as Buck aligns their cocks, hands darting out to grab around his hips, to stop him from shuffling any further towards his groin. His stomach spikes warningly as the hold has Buck toppling forward slightly, pressing even further onto his stomach. "F-fuck!"

Buck whines, long and high, the clarity he had in the lull of his heat waves fading away to something raw and hungry. "'Gonna ride you. Please."

"You—" Eddie groans off a stuttery breath, head dropping back. Fuck, he needs Buck's hands off. "You c-can baby, but I gotta— I have to go piss first. Shit, I'm so sorry. Been drinking so much to keep up with you, but I don't think I've left the bed once in the past day."

"Hold it? Please?" Buck pleads, leaning forward to press messy kisses against Eddie's lips, not taking his hands off his abdomen. Fucking hell, he doesn't know how he didn't wake up jumping out of bed to run for the bathroom.

"I can't, Buck, Jesus, I can't. I need—" He moves his hands from Buck's hips, reaches for his wrists, grabs them with shaking hands. "I need these off, unless you want to get very messy in the next ten seconds."

"Don't mind messy," Buck says, kissing little patterns around Eddie's face and rocking his hips forward. "Love being covered in you."

"Buck," Eddie groans again, long and desparate. Buck huffs out a tiny, little dissatisfied whine against his lips, and leans back onto his heels, hands finally, blessedly, pulling away from his stomach. The pressure immediately relents some, and he relaxes the muscles in his stomach, feeling the way hot pleasure runs back in and up his spine, fucking electric in its intensity.

"Don't know how you even think you can piss like this," Buck pouts, rocking his ass back against Eddie's legs, letting him feel the solid silicon base of the plug filling him up, probably the only damn reason he hadn't immediately sank down onto Eddie's cock. "You're so hard. You won't even be able to dribble."

"You're, hh, you're right," Eddie agrees, clenching his jaw slightly as his bladder aches just at Buck saying the word piss aloud, its own little traitorous agreement. "I'll have to, have to take a cold shower to get soft."

"What?" Buck questions, voice going high and whiny. "But— but that's gonna take so long."

Buck rocks down against his leg again, pushing the plug deeper, even as his face falls open with something like betrayal, like Eddie is purposefully withholding his cock.

"Quicker than if I let it go down naturally," Eddie replies, shuffling to sit up more, bladder spiking with an urgent pressure as he moves. "Plus, I am probably w-well past overdue for a wipe down."

"No," Buck whines again, "But— but I like how you smell. And I need you. I've been waiting all night."

"You've been using me a-all night," Eddie corrects stutteringly. "My body knows how to keep you filled. I'll be q-quick, baby, no more than ten minutes."

"Ten minutes??" Buck cries, scent spiking in distress. "No. No. You can't be gone that long, I— Eddie please."

"I'll be quick—"

"No, no, no— can't you—" He trails off into a long whine. "Wouldn't it be quicker to fuck me first and then piss? You can— you can come quickly, and then you'll go soft, right?"

"Buck, when I knot, I'll have to wait almost a full hour."

Buck bites his lip, and his entire face flushes darker with the wave of heat. "You— you don't have to knot. Just come in me. Please. Fill me up, and I can wait til you can go again to get knotted. We can—" he rocks back against Eddie's leg, "We can use the plug to keep everything in. I just, I just need you, I need you in me."

Eddie's stomach spikes with heat, mingling pressure and pleasure at how bad Buck wants him. Fuck, he wants Eddie almost as bad as Eddie wants him. But— "We've never been able to keep from knotting while you're in heat. Not once. And maybe I can hold it a few minutes, but I can't hold it that long."

"We won't," Buck promises. "We won't, we won't, we won't. Just— just grab my hips if I try to go too deep, okay? We can even— we can even just do the tip, or, or just the first half of the shaft I just," Buck's jaw quivers and he shuffles forward, closer to Eddie's dick. "I need your cum. I want— I want more of it in me. I wanna be so full of you."

"Buck—"

"Please, Eddie," he begs again, scent perfuming around them, sweet and enticing in a way that Eddie knows Buck is doing damn intentionally. "Please. I'll be good for you."

Eddie stares for a second, battling between his own need to pee and his desire to give Buck what he wants.

Only a second, because the winner is the same one it always is when Buck begs so sweetly like that.

"Okay. Jesus. Yeah, okay." Eddie blows out all his breath, like letting anything in his body out will help with the pressure. "But you're not gonna ride me. There's no way I stave off my knot if you're on top. I'm gonna need you to—"

Before the words are even out of his mouth, Buck is rolling off of Eddie, onto his hands and knees with a desperate quickness. His legs splay wide across the mattress, leaving the perfect amount of space for Eddie to kneel between them, a position taken, and taken, and taken again until Buck had memorized it perfectly. His ass cants up, showing off the thick base of the plug, the mottled purple and black one they had only bought a few months back. At the same time, his chest drops down to the mattress, back arching, settling into a damn near perfect presentation.

His skin is pink and glistening in the light of the room, and even as Eddie watches, his hips quiver in the air, hungry, desperately hungry for Eddie to touch him and fill him up.

"God," Eddie breathes out, eyes locked onto the sight of his omega in front of him, eyes tracing from his tangled hair to the mating scar on his neck, down the long line of his back, and to his hole. Arousal steps in front of the urgent pressure to piss, and he immediately knows he made the right choice. To think he would have let himself wait even ten minutes to have this.

"Eddie," Buck whines again, like he's saying please and I love you and I need you all in a single word, every bit of emotion and longing he has shoved into the five letters, a please that Eddie cannot ignore.

Eddie shuffles up onto his knees, biting down on his lips against the echoing desires of his shifting bladder. "I got you, baby. Gonna fill you up, just like you asked."

"Knot," Buck shakes his head, ass tightening as he works around the plug. "Nn, I mean, mean I know. Not knot."

"No knot is right," Eddie agrees, settling behind Buck. He brings up a hand to rest it on the fat globe of Buck's ass, to the left of his hole. The skin is hot under his hand in the way it always is when Buck's mid-heat wave, and he purses his lips sympathetically as the heat radiates up into his palm. He brings up his other hand to the plug and gently wraps it around the base. "Gonna be quick, okay? You'll only be empty for a second. Not gonna let any of what you already have in you out, okay?"

"Kay," Buck whines, dropping his spine into an impossibly deeper curve, pressing his ass back against Eddie's hand at the same time.

Eddie seals his hand that bit firmer around the plug, and without giving Buck a warning or countdown, twists as he pulls the plug out in a single quick pull. It's one of their favorite toys for a reason, fat like a fucking fist, big enough to curve some of Buck's desires for a real knot, but soft enough they never really have to work or strain Buck to get it in or out. It pops out with a slick, filthy sound, coated in a sheer layer of cum and slick that webs across the base and down Eddie's hands as he pulls it away, the fat bulb of it wobbling slightly as it pops free of Buck's hole.

Buck keens, a high, needy sound, and his hole flutters and clenches around nothing, gaping slightly where the knot had him stretched wide. A stream of cum immediately starts to leak down the back of his ass, thick drips of it heading for his thighs, and Buck lets out a sound of distress as he loses some of the bits of Eddie he had in him.

"Empty," he cries. "I need, I need—"

"I know," Eddie says, swiping a hand up Buck's ass to collect the seeping liquid and smearing it across his dick. "I'm gonna give it back to you. Gonna give you more."

He presses his cockhead against Buck's hole, plugging it like a fucking stopper, feeling how much bigger he is even against the stretched gape of his entrance. His nose flares once as he breathes in the intoxicating smell of Buck's slick that surrounds him once again, mouth watering at the scent of his man, a single moment of appreciation before he gets to work. Before he fills him.

And then he pushes in.

Even when Buck is wet like this, stretched and slick and painted with cum, it always takes a tiny bit of pressure to get past the resistance of his entrance. A tiny push, push, push, before his head pops in, swallowed by the flush of Buck's hole, immediately enveloping him with heat and pressure and pleasure. Arousal chills jolt from the base of his spine all the way up his back, spreading like an infection through his nerves, even with just the first inch or two of him buried in.

Buck keens out a broken little, "Uh, Eddie," and immediately tries to rock his hips back into Eddie, shoving the shaft a few inches deeper into his hole. Eddie catches him with a hand on his ass, halting his progress with Eddie buried about halfway deep into him, and Buck whines again.

"Hold on, Buck, h-hold on," Eddie manages, voice tight. "Just— just let me, uh, do it, okay? Don't want to let you get too deep."

The pressure around his dick mingles with the tightness of his stomach, and he curls forward a little bit, hair dropping down his forehead at how much it feels. Jesus. Jesus fuck, the pressure feels like an entirely different beast now, and he doesn't know what—

He kicks his hips forward a tiny bit, burying himself deeper into Buck, and lets out a little choked, "Uh, nn," as he gets that much more of Buck around him. Fuck, he can't even tell if he's just that close to the edge already, or if it's just his god damn bladder emphasizing everything, making it sharp and electric under his skin.

"More," Buck pleads, hands clasping and releasing in the sheets, head tilting sideways to stare back at Eddie over his own shoulder, mouth open in a wet, messy pant, and eyes glazed with pressure. "More, more, more. E-Eddie."

"Gonna fill you," Eddie chokes out, "I will. I will."

He pulls his hips back and away from Buck, watching as his cock glides out, messy and slick with everything already inside of him. Back, and back, and back until just his head is buried inside Buck, listening as Buck pants with the loss, before he shoves his way back inside. Every bit of his brain is queuing him, begging him, to go in. In and in and in, all the way to base, to where the barely there swell of his knot can be encompassed, too. To where he can lock himself, breed his omega, do his job as an alpha.

He barely catches himself before he rocks his knot in, hips stuttering around the three-quarters mark of his cock, and immediately drags himself back out, knowing damn well if he stayed that deep, he would only go deeper. The next thrust is better, only around two-thirds of his length shoved into Buck, and he pants out stuttery little breaths as he settles into the rhythm, out and then in, keeping his knot decidedly away from any temptation.

A consistent rhythm, though, might not have been the best idea. Because a consistent rhythm is predictable.

A few thrusts later, as he rocks himself into Buck, the omega, who has been consistently panting "More, more, Eddie, more," since Eddie sank into, sees the opportunity. And as Eddie pushes himself in, Buck shoves himself back, easily closing the remaining little distance and spearing himself entirely onto the alpha's shaft.

And— and the knot isn't the issue. It feels good, sinfully fucking good to have the most sensitive part of his shaft in Buck, but he isn't close to locking yet.

No, the issue is the way the shock of the impact slams into Eddie's abdomen, sending waves of pressure, pressure, pleasure, pain, across his tight bladder and electrified nervous system, immediately pulling a strangled, "Fuck!" from his throat. He jolts forward, curling in against the sensation, and it only shoves him further into Buck, shoves Buck further back onto him.

And it shouldn't feel good. It shouldn't feel like fucking anything except filthy, but Jesus. He's never felt anything like it before, never even knew it could feel like this. His entire body feels taut like a bowstring, fraying and ready to snap, desperate to cum so he can fucking fling himself to the restroom and chase the release of pressure from peeing that at this point might feel just as fucking good.

He pulls himself back from the tight clutch of Buck's hole, and Buck immediately pants out a "Sorry, ssorry sorry sorry, wanted— shouldn't have—"

"I know, I know," Eddie soothes, voice quivering, hips rocking back to where his knot is outside his hole. "I know you want my knot, I'm sorry I can't, I'm sorry."

"I jus', just want you deep," Buck nearly cries, eyes clenching shut. "I know how long you are, 'nd my body's telling me, 'more, more, you know there's more.' I can go without your knot, but I want—"

He cuts himself off, and Eddie's hips stutter forward. "Just want all my shaft?"

"Yess," Buck replies, voice laden with hunger, eyes flashing back open.

And Eddie— thinks, for a second. Just a second, because that's about all the patience he has. He thinks about how good it feels to be buried in Buck. And how goodbadtoomuch it felt to have that pressure amplified like that. And he thinks about how good of an alpha he'd be if he gave his boy what he wants.

Considers it.

And he reasons, yeah. Yeah, I can pull back before I knot in him.

"Fuck," he says. Then again, "Fuck. Yeah. You just, you gotta stay still, okay? When I pull back, I need you to stay still so I don't accidentally knot you."

"Uh-huh," Buck pants absently. "I'll be good."

"Good," Eddie replies, eyes flicking back down to watch as he pulls his cock back out, then drives it back in deeper. Out again, then even deeper, til Buck's ass hits solidly against his groin. The sensations echo up his system again, but he was ready for them this time, ready to find the unique pleasure in the pain and grab onto it, to chase the heat around his nervous system.

It's— it's fucking insane. And he feels like some kind of pervert, using the tight clench of Buck's body and the slap of his ass cheeks as a way to chase the pleasure of fucking— of fucking needing to piss. But it's indescribable how good it feels, and they're only doing it because Buck begged him, so it's— it's fine. They're both getting what they want, and Buck had mentioned being into watersports once before, so he wouldn't even mind. And this isn't even that, it's just— a happy coincidence. A circumstantial discovery.

He keeps thrusting in and out, solid drives with solid impacts each time, and arousal crests through his system, higher and higher with each one. He starts to feel the barely there catch of his knot as it drags against Buck's entrance, swelling and ready to breed someone, but not yet. Not—

Not. Yet.

It feels too fucking good, and he probably has a good dozen or so thrusts left until he starts getting to the point where there's even a potential of him getting stuck, so he— he doesn't need to worry about that yet. And Buck's making these little sounds beneath him each time the swell of the knot drags past his entrance, punched out pleasure-soaked keens, and how could he take that from Buck when he knows he could give him more?

So he keeps driving in, feeling the way the drag gets tighter and hotter with each thrust, the way the impacts against his abdomen are that much heavier when he has to fight the drag of his own knot, and it's so fucking good. He goes a dozen thrusts more, and he's probably at the point where he should just jerk himself off to completion while half in, but— but he can still pull it out. Technically, and why stop when he can tell by Buck's noises that he loves the swell just as much?

He's a good alpha, and his omega is in heat. He's going to give him everything he can, for as long as he can.

So he keeps thrusting, each outstroke joined by a little muttering of, "One more, one more," greedy utterations, perfect in sync with Buck's pants of "Alpha, alpha, alpha," voice gone soupy and distant, entirely lost to the heat.

He thrusts in a final time, and just by the popping of his knot past Buck's rim, knows that's it, that's the actual last one. He pulls out, feeling the insane drag of his knot past the rim, and stops with his knot just outside Buck's ass, instantly dropping a hand to start squeezing at his knot, rhythmic grabs to imitate the tight clench of an omega's lock. He tilts his head back, abs clenching as he growls, "Gonna fill you, gonna, gonna—"

"Fill me up," Buck echoes, voice wistful, absent of everything but desire. "Yeah. Breed me."

And Buck then, in a move that Eddie really, really should have seen coming, shoves himself back and over the swell of Eddie's knot with the surety of an omega that had never once been denied a lock.

Eddie has a split-second thought of 'Oh shit,' before Buck locks around him, all the muscles in his ass tightening as his orgasm hits in, filling the air around him with the scent of Buck's sweet omega cum and the sounds of his moans. Paired with the milking squeeze around his cock, Eddie is helpless to do anything but come, pleasure lighting up his whole system and black spots filling his vision as shoots stream after stream after stream of hot cum into Buck, knotting swelling out even wider and locking them together as he pumps the omega full.

The orgasm is everything he knew it would be, hotter and more intense than he had ever had before, his entire body sweat-slick and taut with pleasure as he fills him up, hips helplessly jerking into Buck with a reckless sort of desperation he had never experienced before.

But as soon as he crests the high point of his orgasm, vision still dotting with pleasure, he can feel a cold sweat gather along his spine with the realization of how utterly fucked he was. Because in the absence of the all-encompassing heat of his arousal, he becomes all the more aware of the pressure still dominating his bladder. And just holding back long enough to fuck Buck was a miracle; holding it for forty minutes would be—

"N-no," he pants, looking down at where he was pressed flush against Buck, panic flooding his body. "F-fuck, no— No, no. Buck. Buck."

Buck's entire body shudders with a lazy sort of satisfaction, head lolling against the mattress and hole squeezing around Eddie's shaft, milking even more cum from him. "Mm, knotted me. Good alpha. Filling me up."

"Buck," Eddie gasps, strangled, "Buck, we weren't s-supposed to knot, I— I have to pee." His entire body tightens with pain, with the strain of holding back now that there isn't a mounting orgasm to focus on, and he's feeling so much that tears bead in his eyes just at the concept of holding back that long. "I don't know what to do. Oh my god. I— Buck."

"Mm," Buck snuffles a bit, not sounding any less content. "'M sorry, forgot."

"I can tell!" Eddie chokes out, curling in and over himself. "Oh, my god. I don't know what I'm going to do. I can't—"

He reaches a hand down to trace around his own cock, a useless, there-and-gone thought that he could maybe pull himself out that he immediately dismisses. He wouldn't be able to without hurting Buck. God and it—it wasn't like it was when he was hard and hadn't come yet. The internal little block that was holding him back is nowhere to be found, and it feels like untensing his stomach even a little would be like poking a hole in a dam.

Pain spikes in his stomach, and he groans, the sound dragging itself out of him. "I— oh fuck, I can't— I don't know how I'm gonna hold it." He squeezes his eyes shut and feels the beading tears swell up to dampen his eyelids. "Buck."

"'M sorry," Buck says again, the regret in his voice buried behind a mountain of soupy pleasure.

"It's—" Eddie clenches his jaw against the sensation. "I just— I don't want to—"

"In me?" Buck asks, sounding entirely unbothered.

And fuck. There's that out loud. And that— Eddie hadn't put that into words, hadn't even conceived that as an option, but it does something to him. Has his dick throbbing, and his bladder tightening, and guilt sharpening around his eyes because he can't do that, he can't want that, he can't—

Buck huffs a satisfied, almost thoughtful, little breath out of his nose "Y'can, you can fill me up, if you want. I don't mind."

Eddie's stomach lurches dangerously. Eagerly.

"What?"

Buck hums, again, wordless and wanting.

Wanting? Is he wanting for—

"Buck, w-what?"

Buck's eyes finally flutter open to stare at Eddie, pupils blown wide, and damn near fucking hungry. Hungry in the way he normally saves for Eddie's cock.

"Love being filled," he says reverently, vowels liquid in his mouth, slow to take shape. "Love being filled by you. All of you. I'll take your cock and your cum and your spit and your fingers…" He licks around his lips once. "Tasted your blood when you got shot, then again when I bit you. And it was just more of you. I love all of you. All of you in me."

"Buck—" Eddie gasps, filthy, guilty pleasure rushing back into him. He can't mean— He doesn't actually want—

"Bet I'd feel so full, too…" Buck says, wistfully. "All of you flooding me up. God. And you'd keep me full so long, too. Your knots always last so long"

"Buck," Eddie says weakly, "Is that— is that even safe?"

Buck smiles, a lazy, satisfied grin. "Y'wanna find out?"

"I—" Eddie cuts himself off, stomach lurching dangerously. He relaxes his abs unconsciously and feels a tiny trickle of urine escape without his intention, a tiny flash of wet warmth that pools around the heat of his dick.

And Jesus, just that is good. It shouldn't be good. He shouldn't want this. But Buck—

"Fill me up?" Buck asks, sweetly, so sweet and innocent, like he isn't asking Eddie to— asking him to— "Please?"

Eddie stares at him a second, fingers twitching on his hips, bladder pinging with the need to piss. And he knows, in the same way he knew he was going to fuck Buck, in the same way he knew he was going to give Buck his whole cock, exactly what he's going to do.

"Anything you want, Buck."

And he lets go.

It isn't like the few times he's tried to piss while hard in the past, the pushing and pushing and pushing against a wall he can't get past, the barely there trickle of drops barely strong enough to do anything but run down his shaft.

He relaxes, forces all the muscles in his abs, stomach, and groin to calmness, and the effects are immediate. Fucking torrential.

Piss streams out of his cock in an immediate, unstoppable flood. If Buck changed his mind, there would be no putting the cap back on it, no cutting off the stream. The pleasure of it—the relief— was unlike anything he had ever felt before, dwarfing the orgasm from before, mingling with the echoes of its pleasure into something electric and filthy and fucking hot.

The piss floods around his cock, forcing itself deeper and deeper into Buck, and Buck let out such a chest-deep moan of pleasure that Eddie finds himself mirroring the sound, curling over Buck and blanketing him as he fills, and fills, and fills him. It was goddamn obscene, the way he was taking Buck in this— this taboo fucking way that could look so average from an outside perspective. Not a drop of piss leaking out from around his knot, nothing to betray the filth of it, all of it trapped inside Buck, keeping him—

"F-full," Buck cries, legs and arms slipping against the mattress as his limbs went shaky. "Eddie, I'm s-so, I'm so full." A shiver visibly went down the omega's spine as he spasmed against the mattress, caught on Eddie's cock, filled in every way he could be filled. "'M so full of you. It's so— it's so much. It hu- uh."

Eddie moans again, cock throbbing inside of Buck as he keeps filling him, every bit of water he had drunk to keep himself hydrated for Buck rushing into him. Buck's hand curls up towards his own stomach, and Eddie wonders if Buck can feel the pressure, can feel a tautness in his stomach that wasn't there moments again, wonders if there's enough of Eddie in him to pudge his stomach out. It should be a gross thought, but god damnit if it doesn't make his knot swell that much wider as he thinks of himself filling Buck up enough for him to feel from the outside.

Buck moans again, and Eddie chases the feedback of the sound—pisses harder into Buck, giving him every drop he has. And he's sure that later there will be guilt— guilt, and hard talks, and long conversations— for for now he's just an alpha, giving his omega in heat everything he wants. And there isn't any place in the world he'd rather be.

After what feels like minutes, his stream finally tapers off, leaving them both dazed and pleasure-rung on the bed. Buck looks fucked out under him, lax and satiated in a way that normally only ever comes at the very end of their heat, and Eddie feels—

Fuck. He feels like he just had an other worldly experience. He feels like maybe he rolled his eyes and said, "Of course you would," just a bit too fast when Buck mentioned his piss kink when they first got together all those months ago. But more than everything, bone deep and echoing in every part of his stupid wolf brain, he feels like a damn good mate.

He collapses all the way on top of Buck, jostling his cock and feeling the way he is absolutely surrounded by everything he put into Buck, and licks once along the mating seal on Buck's shoulder.

"Shower," he says, breathless. "Both of us. And we're not waiting til I go soft. These sheets are already a mess, and I don't think our mattress protector is that good."

"But I'm so comfy." Buck snuffles into the bed, a sleepy, smug, satisfied sound. He cracks open an eye again and turns to look back at Eddie, expression coy and knowing. "What if I don't wanna?"

"Well—"

Eddie cuts himself off, jaw snapping shut.

And Buck, sleepy and content, and with all the confidence of an omega that knows he has his alpha wrapped around his finger, smiles a tiny, devious little smile.