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Bucky snaps awake with the sudden and intense feeling that something is off. He does the first thing he always does in these cases, even before grabbing the gun hidden by the headboard—he reaches for Steve. Only, instead of finding a warm, solid body, he encounters only air.

Steve, despite his and Natasha’s best efforts, is usually about as stealthy as a panzer. The only times Bucky has reached out and not encountered Steve had been because the blond had been away on a mission or for some other work, and hadn’t gone to bed with Bucky in the first place. He feels a jolt of panic when he realizes that not only is Steve not there, but his side of the bed is cold. His feet are on the ground and the gun is in his hand before he’s even fully awake. He stalks across the room, sweeping systemically and clearing it before moving on to the bathroom, and then the hall. If this were a horror movie, he’d probably call Steve’s name, but it’s not and he doesn’t; just strains his ears to try and detect even the slightest change in air pressure that might indicate an intruder.

:Sergeant Barnes.:

Bucky is too well-trained to jump, but he nearly shoots the ceiling. “Jesus,” he hisses.

:I’m afraid it’s only me, Sergeant: JARVIS says in that droll way of his. :I have been overridden by Agent Romanoff to alert you as to the whereabouts of your mate. Captain Rogers is currently in voluntary residence of Isolation Ward Three.:

‘Isolation ward’ echoes through Bucky’s head for a few long seconds before the rest of the sentence catches up to him. “Voluntary? What’s wrong?” He’s already switching his gun out for a knife and shoving on his boots.

:It appears that Captain Rogers’ fertility cycle has reached its peak, and he wished to experience this in private.:

“What the—Steve’s in heat?”

:Indeed.:

Why can’t the stupid AI just say that? “I thought he couldn’t anymore. Or just didn’t.” The ongoing theory is that between losing his mate and being on ice, his system had been traumatized enough to suspend his heats indefinitely. It’s not unheard of, particularly if the body’s resources are direly needed elsewhere for too long. Seventy years of ice probably counts as ‘too long.’ He guesses they underestimated the serum.

:Captain Rogers began experiencing symptoms as of 0200 hours. At 0230, he locked himself in Isolation Ward Three. Five minutes later, he requested that I list Agent Romanoff as his emergency contact, and I alerted her as to his additional needs. At 0310, Agent Romanoff advised that I was to tell you Captain Rogers’ exact whereabouts should you ask. I have chosen to exercise my discretion when I detected your unusual level of alertness.:

JARVIS’s polite way of saying he didn’t want Bucky to break anything valuable in a panic. He’s not wrong. “Thanks, I guess.”

:You are quite welcome, Sergeant.:

“…Uh, JARVIS? You can open the doors now, buddy.” Bucky stares at the elevator doors, which are unmoving despite the fact that he’s heard the cab slide into place.

:I’m sorry, Sergeant, but Captain Rogers’ request was for privacy from anyone except Agent Romanoff, outside of a medical emergency.:

“Then why the hell did you tell me—”

:So I cannot possibly tell you that the north-west stairwell has the optimal path for someone of your skillset to descend most rapidly to the medical floors. I would also be against protocol to suggest for even a moment that all isolation wards are equipped with observation monitors and intercommunication devices used for emergency purposes, and for which Agent Romanoff has the keys. Agent Romanoff has strictly forbidden me from issuing you these overrides, and is definitively not waiting for you at the exit of the north-west stairwell, and she does not have coffee. Completely aside from this conversation, how do you take your coffee, Sergeant?:

“Two sugar,” Bucky says distractedly, already bracing his flesh hand against a railing. It’s the work of a moment to swing-and-drop his way down to the appropriate medical floor, and he’s barely landed when the door swings open in front of him.

“Took you long enough.” Natasha lounges with exaggerated nonchalance against the doorframe and takes a too-casual sip of his coffee. That’s how he knows she’s worried, because otherwise she wouldn’t be trying quite so hard to project that she’s not. She lets Bucky snatch the cup from her hands and chug it down hot—it only wakes him up due to the placebo effect, but Natasha knows how important it can be to have some small semblance of normalcy during an emergency.

“Communication for Iso-Ward Three could be malfunctioning—” Above them, JARVIS makes a mildly offended noise. “—because I seem to have unlocked the communications and can’t lock them back down. The door lock still works, however,” she adds pointedly. Bucky holds back a snort of derision. As though he’d enter against Steve’s will, especially while he’s in such a vulnerable state. He appreciates Natasha’s protectiveness of Steve, though. “Don’t mess this up, Barnes.”

He can’t promise that he won’t, because that would be stupid and meaningless. “I’ll try,” he says instead, and accepts her approving nod. He strides down the hall to the observation center without even waiting to see if she leaves or not.

Audio for now, he decides when he gets to the panel. He flips the switch and immediately has to tamp down the urge to rush off and tear someone’s throat out when he hears the low whines of pain picked up by the room’s mics.

“Steve,” he murmurs. There’s a pause, then a gasp, and the kind of silence that Bucky remembers means that Steve is determined to suffer quietly, even after he’s been found out. “Stevie, you might as well talk to me. I didn’t know you were going into heat.”

“Didn’t know either,” comes the rough reply. He sounds hoarse and maybe dehydrated. He wants to ask if there’s water in there with him, except that he knows that neither Steve nor Natasha (nor JARVIS, for that matter) are that dumb. There’s water in there; it’s just a question of whether Steve is drinking it or not.

“You knew enough to sneak out of the room, baby.” Bucky works to keep his voice low and soothing, pointedly not raising it in anger or accusation. Neither of things will help either of them right now.

“F-figured it out yesterday. But I thought it was a fluke, Buck.” Steve will be ashamed to remember later that he whined.

“You could’ve woken me up, hm? You don’t have to go through this alone.”

“It’s not so bad,” Steve chuckles weakly. It convinces precisely no one. “I just… didn’t wanna inconvenience anyone, is all.” There’s a cut-off gasp, and a small strand of Bucky’s patience snaps.

“Steve, I’m turning on the observation cameras, okay?”

“No!”

“I need to make sure you’re taking care of yourself. That you’re not in pain.”

“I got this, Buck.” And his voice sounds stronger, but with Steve it always has right when his back’s up against the wall.

He snorts. “Pal, I got amnesia, not stupid. Let me see? Please?”

It’s either the please or the sarcasm that does it. Steve grunts his assent a moment later, and Bucky flips the switch.

The covers on the cot inside the small room are completely askew, trailing on the floor and even the mattress sheet rucked up from what Bucky is assuming was Steve’s pained writhing. He’s huddled in a corner now, clothes obviously gone but with part of the flat sheet covering him, pulled so tight across his shoulders that it seems fit to rip. Bottles of water, some empty and some full, are scattered across the floor, and what looks to be a bucket of ice lies on its side. On the video feed, Steve lifts his head and looks muzzily around, scanning for the cameras he knows must be inside. Part of Bucky wants to laugh—does he really think the cameras will be so easy to spot?—but the rest of him wants to cry a little. Even in his big body, Steve looks so small and defiant, frightened but determined as ever to tough it out alone. He took more than fifteen years to try and break the man of that habit, and he’s not about to let all his hard work be undone.

“That doesn’t look like you’ve got it, Stevie.”

“Shut up,” Steve grumbles, glaring at one of the cameras. It seems like Natasha’s painstaking training in surveillance paid off.

“I ain’t gonna lie: looks kinda bad.” He can see a few toys caught up in snarls of blanket, and Steve’s whole body is flushed. The vitals readouts on the console indicate a temperature high for even Steve’s enhanced metabolism. “Why didn’t you just say something, doll? It wouldn’t be the first time I spent a heat with you.” He wants to add ‘right?’ at the end of it, just in case he’s wrong. Just in case that’s one of the daydreams-as-memories he has stashed around his brain sometimes. But he’s 95% sure that his post-Hydra brain isn’t creative enough to come up with the vivid scents and sounds conjured when he thinks about the omega’s heat. He and Steve have been slowly working up to penetrative sex, and it always seemed more important to be intimate rather than rushing things. He wonders now if it would have been easier if they’d already taken that extra step.

“Your files… Hydra…”

Bucky isn’t really sure what Steve is trying to say. He knows that a lot of the team probably have secret meetings (or at least pass each other notes) about the best ways to peacefully re-integrate him and navigate through the minefield that is his memories and his past. But he’s not sure what in this particular instance has Steve balking to even talk to Bucky about something they’ve already shared.

“I didn’t want to force you,” Steve chokes out.

It’s a little stunning, actually. Bucky’s first thought is confusion—what? Why would Steve think Bucky would be forced to do anything? Then incredulity—is he serious? When just about everyone else insists that alphas force themselves on omegas all the time? When Bucky would be in the position of power? Following hot on the heels of that thought is shame. Of course alphas can be forced, and in a number of ways. An omega using their heat to leverage biology is one of those ways, if the alpha is particularly compatible or in rut, or susceptible to suggestion.

And then he understands.

“Oh, Stevie.” He’s read his files; added to them, even. He hadn’t thought about it until now, that little line that read ‘forced breeding.’ The phrasing is cold and clinical, and that’s how he prefers to think of most of his experiences under Hydra’s thumb. But there could be myriad ways to interpret that, and Steve, the self-sacrificing idiot, decided his interpretation must be right without consulting Bucky on the matter. Maybe he would have talked to Bucky about it after this heat, but maybe not—Bucky won’t take that chance.

“I wasn’t forced the way you think. Hydra suppressed me—milked me when they wanted a… a sample, or a… contribution.” Easier to think of it that way. He also knows that none of it ever took, because he can remember the escalating number of punishments meted out to him. “They tried to send someone in, once…” The one and only time they’d actually allowed him to rut, hoping that an actual coupling, complete with a knot, would take. “I got out of control. Killed them.” His fragmented memories tell him that the poor thing cried for death; sobbed and pleaded with the guards to stop, to let them go, anything but this. Bucky had been quick and merciful: a simple snap of the neck and the poor soul was gone. He hadn’t even needed both hands to do it. Hydra never tried again.

“Lying,” Steve pants.

“I’m not.” His words come out sharper than he intended, and Steve flinches back. Taking a second to compose himself again, Bucky gentles his tone. “I’m not lying. I wouldn’t do that, Stevie. Not about this. Not about something that affects us.” He waits while Steve shifts restlessly, small whimpers escaping his throat while he weighs Bucky’s words.

Finally, the blond nods. “I believe you.”

“Then you’ll let me in? Let me help you?”

Another long pause, but Steve nods again, biting his lip like he might cry. The air whooshes out of Bucky’s lungs. Thank God.

He barely has the presence of mind to shut down the feeds before he’s rushing down the hall and knocking on the door. The seal is good, and he can’t smell Steve at all despite the pheromones he has to be exuding like crazy. The secondary door behind him closes before the seal on the main door even cracks open, but as soon as it does Bucky finds himself trying to wedge his metal fingers in there to hasten the motor along. It’s an instinctive thing, his brain registering distress and pain of a member of his pack and reacting to it immediately. JARVIS cuts sternly through his little trance.

:Sergeant Barnes, I will have to ask you to wait patiently while the door finishes opening or else risk damaging the seal. I assure you that it is opening at maximum speed.:

Bucky gets himself under control, fists clenching and unclenching rhythmically so that the arm whirs with the recalibrations. As soon as the door is open enough to let him squeeze through, he does. He can hear it reverse direction to close again, and if a computer could execute such an action sulkily, he suspects that JARVIS just did.

“Oh, Stevie.” He shucks his shirt and shoes before he even approaches, giving Steve the skin to skin contact the omega will crave. He gathers the blond up like he’s five-four and a hundred pounds all over again, cradling him in his arms while he kicks and drags all the blankets back towards the bed. Steve huddles close, arms tight around Bucky’s shoulders and neck, nose pressed to his scent glands. It makes Bucky so intoxicatingly hard, but years of dedication of caring for Steve win out. He lets go only long enough to wrench the bed to its side and drag the mattress all the way to the floor, wedging them into a soft, protected corner of the room. He orders JARVIS to dim the lights, and after a few seconds of Steve huddling in his arms, he can feel the omega’s trembling begin to ease off.

“There you go,” Bucky coos. “Can you drink something for me, baby? Can’t have you passing out.”

Steve whines and sticks his nose aggressively against Bucky’s throat again, lapping at the gland there as though he can taste the pheromones the alpha is pumping out.

“That’s not an answer. I want to take care of you, Stevie. Can I?” It hurts a little to have to pull Steve away, gripping his chin tightly to force blue eyes to meet his. “I’ll get everything at the same time; we won’t have to leave again if you don’t want to, I promise, but we need water and food. Ten seconds; you can count them out loud.”

Steve tries to tilt his cheek into Bucky’s touch, but the brunet gives him a tiny shake. Steve is covered in sweat and he doesn’t think the omega has drunk much in the hours he’s been here. “Count.”

It takes a few tries before Steve finally croaks out, “One…”

Bucky bolts for the supplies, snatching extra towels and a few toys while he’s at it. Steve is only at a shaky ‘seven’ by the time Bucky enters, dumping half his prizes into their makeshift nest and using the crates of food and water and sports drinks to barricade the last side of their fortress.

“Okay,” he soothes. “See? I’m back now. All better.” He lets Steve crawl back into his lap as he unscrews a bottle, holding to the blond’s lips. “Drink this. All of it.”

Steve looks like he’s going to refuse, but Bucky starts up a low warning growl and Steve takes it instead, looking a little surly. Once he takes a sip, however, he’s suddenly chugging the entire thing down. Bucky has to put his hand over Steve’s to control his pace of the second bottle of water—any faster and he might make himself sick.

“Good job.” Bucky rubs the blond’s back comfortingly, urging him to take smaller sips. He’d try to get Steve to eat, but he’s guessing the omega is in enough distress that he’ll throw up most of what he consumes. “That’s better. Thank you, Stevie.” In response, Steve practically purrs and presses open-mouthed kisses into Bucky’s scent glands, sucking a bruise there. Bucky lets him, a new spike of lust jolting through his system.

“What do you want, hm?” Steve whimpers in his arms and he moves to soothe him again. “I know. I know it hurts, but you have to use your words. I want to help you—what do you need?” He fumbles for some of the supplies he grabbed along with the food. “It looks like Natasha’s got you well-stocked, huh?” He’s not new to the concept of sex toys, and he knows enough to be able to guess at most of the functions of them even without having seen these particular ones before. True to form, they’re also all very sleek and tasteful. He eyes one with a few buttons on it. “Uh, I think this one vibrates? That sounds nice, yeah?”

Steve’s only response is to nip at him, so he tries again. “This one…” Okay, it has him stumped for a second. Steve pawing at his bare chest really doesn’t help. “I think the knot inflates,” he manages. “That sounds…” Oh, God, he can see it in his mind’s eye, how Steve’s hole would look, glistening and stretched around the dark rubber, skin flushed and ass full. He swallows hard. “Fun? Looks fun. What do you think?”

“No,” Steve rasps. He sounds like simply talking is a huge effort, like he’s moving his mouth through sheer force of will. For all Bucky knows, he really is—it’s not like the brunet has ever had a heat.

“Sweetheart, you don’t have to suffer like this. It’s not like when we were kids, you know?”

“You.” Steve curls his hands into Bucky’s shirt. “Wan’ you.”

“Oh, Stevie, sweetheart, you’re heat-sick. You don’t mean that.”

“Yes I do!” Steve snarls. It’s not the most un-omega thing he’s ever done, but it’s up there. Bucky loves him more for it. “Summer ‘35. Prospect Park. I wanted—you said—” Steve curls in on himself, hands pressed to his lower abdomen as he rides out another cramp.

“I said I’d be honored to help you through your heat,” Bucky remembers. “But then you didn’t until you were twenty, and the docs said a full knot might tear you up.”

“Still wanted it. Wanted it since I knew I could,” Steve pants. “So don’t give me no bullshit about not knowin’ what I’m sayin’. Been sayin’ the same for…” Bucky can see Steve try and fail to do the math in his head. “…too long.”

The pleading goes through him like an arrow right through the heart. He promised he’d do anything to help, and the memory Steve offers him rings with the odd clarity that always tells him it’s not a fake one implanted by Hydra. “I know, Stevie,” he soothes. “And I still wanna be that guy for you. But—”

“A bond, too,” Steve whispers feverishly into Bucky’s skin. Bucky’s heart stops cold in his chest, and starts back up double-time just as suddenly. Steve is crawling on top of him, practically tearing off the alpha's pants now that Bucky has given him consent. His hands roam across Bucky’s skin frantically, like he has to touch or he’ll fall apart. He either doesn’t notice or care about the way Bucky’s voice strangles in his own throat.

“B-bond?” Bucky’s eyes nearly cross for a moment when a particularly well-aimed twist of Steve’s hips has his hole slipping directly on top of Bucky’s cock. He sucks in a deep breath and seizes Steve’s waist, fingers digging in hard to keep the blond in place. “Bond?” he repeats.

“Wanted it so long,” Steve mumbles, nuzzling sweetly at the scent glands on Bucky’s neck. “Always.”

There’s a long silence, which Steve seems to take as a ‘no,’ His gaze clears for a moment, and he looks earnestly into Bucky’s eyes. “We don’t have to. ‘S a lot. ‘Specially with a—with me.” There’s a flicker of hurt on Steve’s face, telling Bucky more plainly than words that the blond is recalling any of a number of insults Bucky can remember being hurled at him in their youth. Things like runt, or defect. But Bucky never thought that. Steve has always been perfect. They just don’t make ‘em like that anymore, he remembers thinking, even back then.

“I want it,” he hears himself say. He meant to tell Steve they should talk about it; that Steve can’t possibly want someone like Bucky—damaged goods. He’d be better off with someone else. Someone still worthy of a man like Steve Rogers, who is stubborn and kind and a little shit when he wants to be, but good overall. If you pried him open, Steve would shine like gold. Bucky’s not sure some days if you’d find anything at all inside of himself but a dried-up husk. But what little there might be, he thinks, would be filled with love for one Steven Grant Rogers. So his heart speaks without consulting his brain. “I’ve wanted it for a long time, Stevie. Before and after. That’s what it always meant, right? End of the line?”

It can’t be wrong if it makes Steve smile like that, like a flower opening to the sun. “Today?”

“Today,” Bucky confirms, and Steve promptly wiggles out of his grip and shoves him down roughly, Bucky’s head barely missing one of the crates of water boxing in their little fort. Steve is laughing and he finds that he is, too. The laughing turns into giggles and then peters off into the occasional chuckle, until it’s faded away completely, subsumed by the soft sounds of kissing and skin sliding against slick skin. Steve loses his patience again soon, apparently hitting the end of his endurance now that Bucky is here to help him through it. He presses one of Bucky’s hands—the metal one, the brunet thinks wildly—to his waiting hole, already slick and ready. Bucky make sure anyway; slips a finger in and, when Steve only moans and nods and pushes back, wedges a second one in as well. It’s barely a challenge, and in less than a minute Steve is whining and wiggling, trying to sneak his own hand behind him until Bucky catches on and bats him away.

“I’ve been waiting for this, doll.” Bucky gives Steve a sharp nip in reprimand, although his punishment is maybe compromised by the kiss that immediately follows. “Lemme do the work this time. I want everything.”

To satisfy his omega, he slips in a third finger, carefully stretching him open even though it seems like Steve’s body is more than ready. Steve starts whining again, and then making pained noises when Bucky stretches him just a little more, swallowing hard against his own lust that demands he sink into his omega now.

“Sweetheart, did I hurt you?” he asks softly, smoothing a hand down Steve’s side.

Steve shakes his head adamantly. “No, but I need it now, Buck, please. Need it so bad.” Bucky makes sad crooning noises, realizing Steve’s distress comes from his heat symptoms and not the brunet’s careful ministrations. Or, rather, that Bucky is maybe being too careful; too slow, when Steve’s body has been primed for… possibly hours, now, although Bucky has no way of knowing when he hit full heat, or how long they’ve been here together.

“How do you want me, darlin’?” He has to resist the urge to lick the slick off his fingers, because if he does, if he tastes it and it’s anywhere near as good as Steve smells right now, he’ll go straight for the source and not stop. He’ll have plenty of time to explore that option later, when Steve isn’t practically crying for relief.

In response, Steve rolls onto the floor and onto his back, spreading his legs wide and looking pleadingly up at Bucky. The brunet bites down on a moan and reaches for a pillow, tucking it under the small of Steve’ back almost before he knows he’s doing it. Steve spares a smile for him before zeroing in on his cock, already dark and dripping, and it would be funny if he wasn’t so turned on.

He means to go slow, he really does. And it starts off that way, sliding in the tip easily and Steve sighing and relaxing, Bucky trembling with the effort of being gentle. Apparently, though, Steve doesn’t want gentle. What he wants is Bucky. In a show of serum-enhanced dexterity (which Bucky greatly appreciates), he hooks one leg behind Bucky’s ass and the other just above his hip and twists just so and suddenly Bucky’s in to the hilt, a guttural moan punched out of him at the tight heat of Steve’s channel. He gives a full-body shudder and fights not to come immediately, digging his hands into the blankets bracketing Steve’s shoulders.

“Jesus Christ,” Bucky gasps. “Warn a guy.” But it’s said weakly, with no venom at all. Steve shakes his head.

“I told you I wanted you,” he says, like that should explain everything. He undulates his hips, doing his damnedest to get more of Bucky in him, and Bucky can feel the achy sensation of his knot swelling. He’s never (that he can remember) had it happen so soon.

“Move, Bucky, please.” Steve smells sweet and fresh and so enticing that Bucky buries his face in the join of Steve’s neck and breathes in sharply while he pumps his hips. Lungs full of that addicting scent, feeling drunk with it, he sits back up and hitches Steve’s legs more comfortably around his waist, then grabs Steve’s hips.

“I’ll make it feel better, doll,” he murmurs deliriously. “I promise, no more hurtin’.” Mentally bracing himself, he pulls back as far as he dares and thrusts back in, holding nothing back. The sound Steve makes sounds like pain until Bucky looks down to see him open his mouth on a silent scream and come between them long and hard. The brunet’s eyes go wide as he takes in the sight below him, belatedly resuming the rocking of his hips, working Steve through it. Even after he comes, Steve’s erection barely flags, his body shuddering for a moment, eyes glassy even as he urges Bucky to keep moving.

Bucky shudders all over and curls over Steve’s prone form, bracketing Steve’s head with his hands and landing a dirty, sloppy kiss as he drives himself harder into the willing body underneath him. It seems like that’s all it takes before Steve is keening and coming between them again, his hole clenching tight like it doesn’t want to let him go. He can feel sweat dripping down his face and spine; can feel his orgasm pulling at him; can feel his knot swelling, threatening to pop at any moment, and for once it feels almost like pain, the swelling too fast, soothed only by the furnace-heat given off by Steve’s body. Is this what a rut is like with an omega in heat? It hurts and it’s beautiful all at once, and he forgets for a moment that they haven’t even reached the peak yet.

Steve claws at his back, breathing heavy into the air between them. “Gimme,” he mutters. “Bucky, please.”

“Soon, sweetheart.” Bucky repositions his hands so he can stroke a thumb over Steve’s face, across a cheek and pressing into the soft flesh of his lips, where Steve turns his head to suck the digit into his mouth lewdly. Bucky can feel the hot huff of breath on his skin every time his pumps into Steve, holy God, in charge of even his damn breathing. His Stevie, his omega, is so prefect, so trusting. So vulnerable. Bucky feels a surge of protectiveness so fierce it steals his breath away.

His face isn’t damp with only sweat when he tucks it into the crook of Steve’s neck, the salt of tears mellow on his tongue, combining with the honey-sweet scent of Steve’s unique omega scent, so strong Bucky can taste it. “You’re sure you want the bond?”

“God, yes,” Steve breathes. His head is still thrown back, exposing the long line of his neck, offering himself up wholly to the man atop him.

“One more time, darlin’,” Bucky breathes. “One more time, and then I’ll give you everything.”

Steve’s breath hitches, grasping Bucky’s back hard, like he can take all of the other man into himself. And Bucky wants that, God he wants it. He pistons his hips harder, lewd, wet noises filling the space between them. When Steve’s breath rasps in his throat and a thin, keening whine reaches Bucky’s ears, he knows his partner must be close. He laps around Steve’s throat, looking for the slightly swollen glands there, knowing he’s found his mark when the taste suddenly becomes sharp and clear, like a beacon calling him, resonating deep in his bones. He parts his teeth delicately, putting hardly any pressure at all on that spot, but it makes Steve gasp and clench his teeth.

“You too, Stevie,” Bucky mutters. He moves a hand to cradle the back of Steve’s head, leading his face to the crook of Bucky’s shoulder. After a moment, he can feel Steve nose around; can feel the shudder in the blond’s body as he puts his mouth gently over a place that makes Bucky feel like electricity is sparking all over him. “Last chance,” Bucky murmurs into slick skin. And then suddenly—

—Pain, flaring up hot and bright, and Bucky’s body reacts by clenching his own jaw, feeling his teeth pop through elastic skin and sink through hot flesh until suddenly the sense of Steve erupts inside of him, the slightest scratch of his canines on the scent gland enough to send him hurtling over the edge. He can feel his knot swell and lock them together; can feel Steve’s inner walls stretch to accommodate him, spasming and milking him as he comes and comes and comes. His mouth fills with the metallic tang of blood and his veins surge with molten pleasure so intense he feels like he’ll burn from the inside out.

The last thing he has time to think is that things will never be the same, and he wouldn’t want it any other way.