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(Far From) The Optimal Response

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Tony startles awake when the health monitor alarms from Barnes’s arm go off. Their fading signal means one of two things: Barnes is off-planet beyond reach of Earth’s satellites (not likely), or Barnes is in critical condition and needs extraction.

Tony quickly realizes he’ll need to extract himself first. He’s tied up on the floor of a cell that looks like part of a medieval dungeon, and he can see himself through the camera in the corner behind him. The last thing he remembers is having dinner with a prince who hoped Tony would sell him some old weapons designs—because Stark Industries doesn’t make weapons anymore, of course, but surely there are some old specs Tony could be convinced to part with?—and saying “No,” and the prince graciously accepting his answer, and conversation continuing as they tucked into the main course.

Drugged then. Well, thanks to his modified version of Extremis—which no one knows about but himself, Rhodey, and Pepper—these assholes don’t know what they’re dealing with, or just how fucked they are.

Tony makes friends with the security camera, follows it to connect his brain to the entire facility, takes stock of what he’s working with, and within ten minutes he’s freed himself, locked down the facility, copied all its data to his servers and fried all the originals and every electronic in the building—and left no trace of his ever being there. It wouldn’t have taken that long had his body not still been cleaning itself of whatever toxins they fed him, but the signal from Barnes’s arm is still strong enough for Tony to find him on satellites while he summons his closest RT housing unit. He’s en route to snowy Colorado to rescue one of his two unwitting mates barely seventy seconds after stepping outside.

He finds Barnes caught in a winter storm high in the Rocky Mountains, rank with pain and distress, passed out with his legs stuck in a frozen pond and his vitals dangerously low. The arm’s power has been diverted to helping keep Barnes alive, hence the fading signal. Tony helps it out by cutting Barnes loose and flying them to the nearest human shelter he can find: a small, isolated cabin.

Could he fly them out of the storm? Probably. Would Barnes survive the trip back to the kind of medical facility ideal for a super soldier with all his extremities intact? Highly unlikely.

Tony sends an update and the old hunting cabin’s location to Sharon and Shuri with a thought, gets a fire started, drops every pillow and piece of bedding he can find in front of it, and methodically strips and dries Barnes before turning him into a blanket burrito he rolls to face the flames.

Barnes isn’t even shivering. Tony decides to give it a few minutes before he deems more drastic intervention necessary.

He finds tea and a hanging kettle and fills it with snow for later boiling; maybe he can get Barnes to drink some without waking him up—that should help a bit.

When nothing else in the cabin seems immediately helpful, Tony looks back down at Barnes.

Out cold. Too still. Skin tinged the blue-gray of his eyes.

Tony decides blue-gray isn’t nearly as pretty on Barnes as a skin color. After a few mental calculations, he realizes there’s nothing for it. Huddling for warmth roasting in an Iron Man two-person cocoon sounds like what Tony’s going to do with the rest of his afternoon (even though his internal clock says it’s four a.m.).

He hopes Barnes doesn’t wake up while Tony’s still here; he prefers that Barnes and Steve don’t know he’s the one who’s been helping them out of tough scrapes. Or that he’s their mate. Fewer awkward explanations necessary that way. And apologies. And interactions with Barnes while he’s conscious; no one wants to feel like they owe the man who nearly killed them in a blind rage.

Tony’s grown a massively unfortunate crush on Barnes to rival his crush on Steve since he began monitoring them on missions and into their aftermath (wherein he rats them out to insure they get adequate medical care, and eat enough to replenish their energy as required by their super metabolisms). It’s just Tony’s luck alphas, betas, and omegas became a thing when they un-did the Snap, and he’s an omega with two alphas who’re already taken with each other in a way Tony can never hope to match. Two alphas he’s also on the outs with—entirely and irrevocably, with Barnes. While he and Steve are friendly, and Tony’s mostly put Siberia behind him, attacking Barnes confirmed every bad thing Steve could possibly think about Tony and he knows it, whether or not Steve ever cops to it. It’s even worse now, knowing those are his mates he nearly killed. Not that he knew it until the first time he covertly flew in and helped them while they relocated some unfortunate for their special brand of witness protection program. Tony’d long since stopped blaming Barnes by that point, even come to admire him and find him attractive, but finding out they were mates was both vindicating and crushing: Tony had not one, but two mates, he wanted them both, and thanks to his own actions, he could have neither.

Tony hasn’t told anyone they’re mates, but he did tell Pepper about his crush on Barnes before he knew. Pepper says being able to feel attraction, admiration, and sympathy for the man who killed his parents makes Tony a good man. Tony isn’t so sure that’s true, but doesn’t want anyone else judging him for it, so he keeps his contributions to the shadows and makes sure never to let Steve and Barnes see him.

Thankfully, Sharon Carter and Shuri told Barnes and Steve that Tony’s contributions to their Leverage-esque WitSec program are that of a consultant who prefers to remain unknown and unacknowledged, and the two have been wise enough not to investigate despite their curiosity.

Although it’s unfortunate, Tony is thankful Barnes is still out cold—literally, goddamn it, he’s not thankful for that last part—so he feels less trepidation when he strips out of everything but his briefs, turns Barnes’s back to the fire, un-swaddles everything but his arm and fun bits, pulls Barnes’s chest against his, and configures his suit to cocoon them both and maintain a warm seventy-two degrees Fahrenheit with help from the fire.

Barnes’s freezing skin is uncomfortable, and then an unwelcome relief as Tony gradually cooks like a lobster inside the makeshift red shell. But Barnes’s core warms too, and when the shivering starts, Barnes’s arm signal stops tapering to nothing, and Tony hooks the suit into it with a thought to give it a little charge until Barnes’s body is fully functional and can pick up the slack as per the arm’s design.

Once that’s done, the lateness of Tony’s internal hour, the fatigue of fighting off enough drugs in his system to knock him out despite his Extremis modifications, the worry he wouldn’t be able to give Steve back his boyfriend with all his fingers and toes and other bits, and the soothing presence of his finally-content alpha filling his nose and wrapped around him, all collect like boulders in Tony’s skull that weigh him down into a heavy sleep.




Bucky Barnes wakes up sweating, trapped in a red and gold shell with no idea where or when he is, and wrapped around the elusive mate whose scent has dusted his skin every time he passed out in peril and woke up safe for the past year—him and Steve both. The mate who, frustratingly, refused to reveal his identity or stick around long enough to talk.

Their mate, apparently, is Tony Stark—who’s lying curled up in his arms. He’d think he were dreaming if he couldn’t feel sweat pooled uncomfortably at the bend of his neck, inside his elbow, and on the backs of his knees. The last thing he remembers is fighting the panicky memory of cryo while trying to pull himself out of the ice during that storm, and telling himself not to sleep, don’t you dare go to sleep…

And now here he is, famished, but warm and alive and staring bleary-eyed at Tony Stark’s sleeping face. Stark smells so good. But also, so sad. He looks softer than last time Bucky saw him—in a bunker in Siberia, jagged with rage and heartbreak, trying to kill Bucky for doing the unforgivable. But even without that or the bravado he displayed in the airport and bunker, Stark still doesn’t manage to look peaceful. An air of weariness hangs over his sleeping face, and sadness colors his heady scent concentrated by this metal cocoon and their sweat and proximity. Bucky wonders how much of that is his fault. It can’t be doing Stark any favors touching Bucky, saving his life. Stark must’ve known they were mates, and he stayed away for a reason. It’s not hard to guess what that reason is.

The familiar scent also makes Stark the mysterious consultant Sharon mentioned. If so, it’s no wonder Shuri wouldn’t even give him a hint, and JOCASTA’s systems mysteriously “failed” when they asked for her help figuring out who it was. Stark’s probably smart enough to hack electronics well enough for some of the deus ex machinas Bucky’s been treated to during some missions’ hairier moments, too. And he’s rich and connected enough to send evac and medical teams at a moment’s notice to pretty much anywhere, and drone-drop gigantic takeout orders to crazy locations. Stark and Steve are still friends, still care about each other even though they don’t talk much. That’s probably why he’s willing to help Bucky even though he obviously doesn’t want to be mates.

So now Bucky knows he owes his life to a man he orphaned. Who apparently doesn’t want to kill him for it anymore. Who’s apparently hero enough to save even people who hurt him as badly as Bucky did. And is selfless enough not to want anyone to know how kind he is, despite the arrogance and showboating he’s known for. It’s one thing to hear Steve say things like that about his friend Tony, another to glimpse that side of Stark for himself.

Steve misses Stark a lot, and Bucky likes when Steve talks about him. He’s got a morbid curiosity about the man he hurt, who broke the law to try to help him and Steve when nobody else could anymore, and who’s beautiful and deadly as a panther and sharp as a cactus, and wields a bulletproof poker face; who hates him enough to want him dead but didn’t hunt him down even though Bucky knows he could’ve. The man who helped Steve save the universe, who gave Steve hope when he had none.

God, why’d Stark have to be so pretty on top of all of that? Bucky’s close enough to count his eyelashes, see the white of his teeth and a flash of pink tongue through his parted lips, feel the rise and fall of Stark’s breath against his chest. He should let go, get up and find his clothes and leave before Stark wakes up like Stark probably wants. But…he’s stuck. The shell won’t move.

He’s trapped right where he wants to be, right where he doesn’t deserve.

Stark shifts in his arms, and worry seeps into his scent. Bucky strokes his back and shushes him, wills Stark to sleep a little longer. He looks like he could use it, and Steve says Stark never slept enough. Miraculously, Stark tucks his head under Bucky’s chin, noses into his neck, and quickly quiets. Bucky feels proud despite himself. Maybe Stark being his mate changes things? Maybe that means it’s okay for him to want and admire a man he—

No. He can’t think about that. Steve’s his mate too, and he’s sensitive to Bucky’s sadness, gets restless when he catches it in Bucky’s scent. Sometimes Bucky’s distress wakes him up. If Stark’s anything like Steve, Bucky needs to lie still and enjoy this while he has it. Think happy thoughts.

He hooks Stark’s legs closer and lets himself drift.


When Steve opens the door to the cabin, hiking backpack laden with enough food for three super soldiers—far too much, but JOCASTA ordered and she’s generally spot on in her assessments—the first thing that hits him is the wall of heat.

The second thing’s the amazing scent.

It smells perfect inside the cabin. Like Bucky’s room in the safehouse when their mysterious mate fixed his arm while he was unconscious, but magnified a thousandfold. Steve closes the door as quickly and quietly as he can to keep out the cold, and keep from disturbing the two men nestled together under an oblong armor blanket in Steve’s favorite shades of red and gold.

Bucky and Tony are under there. Huddled close like they’re made to fit together—because they’re mates, and according to the universe that means they are. The mate who’s eluded him and Bucky for almost a year now is Tony Stark.

Steve gets them both.

God, he can’t stop smiling.

He wished it was Tony but thought it couldn’t be—Tony’s such a closet romantic he’d’ve shown up at Steve’s door the minute he knew, Steve’d been sure of it. And while he still feels awful about lying to Tony and how things went down in Siberia, Tony isn’t mad at him anymore, they made up and saved the universe and parted amicably, albeit not in person after the un-Snap. If they’d met in person, Steve would’ve known they were mates and tried to keep Tony with him—he’d’ve finally known he had a chance.

Realizing they were mates was the impetus he and Bucky’d needed to get together. Realizing they had a third soon after—a third who was avoiding them—had been maddening. They both agreed: nothing smells better than the combined scents of their mates. If they got a little reckless after learning their mate might show if they were in dire straits, they didn’t acknowledge it. Steve was sure if they could just catch whoever it was long enough to talk, they could work something out.

And it’s been Tony all along.

Tony’s not just helping Steve, either. He’s been helping Bucky. The one person Steve worried would be a dealbreaker, and Tony’s lying in his arms not ten feet away. This whole time, Tony’s been fixing Bucky’s arm and rescuing him from terrifying situations and ensuring he’s well-fed and gets good medical care, and probably using JOCASTA—who he designed—to slip them things like Bucky’s favorite blanket, and info for the therapist they both see, and probably other things Steve doesn’t even know about.

In hindsight, he wonders how he thought it could be anyone else. Those are such Tony things to do. Forgiving people, helping people, fixing people, and dodging the credit—that’s all textbook Tony behavior. And Tony’s good with tech. How he managed to hack an entire power grid fast enough to save them is beyond Steve, but Tony does a lot with tech Steve doesn’t understand, and God—their other mate is Tony.

Steve tries not to worry Tony’s still here only because he fell asleep. Tries to take hope in Tony’s willingness to warm Bucky with his own body and reshape his armor just to save him. He snaps a picture of them with his phone, their heads tucked against one another in slumber. He makes it his wallpaper and sends it to Bucky. Then, nervously, he sends it to Tony too.

He doesn’t get out the food and put it on the table—he doesn’t want the smell to wake them. Instead he sits on the couch facing the fireplace of smoldering embers and watches them sleep, memorizes the image from a thousand angles so he can draw it later, can remember their perfection perfectly.


Steve’s happy scent meshing with Stark’s nascent contentment wakes Bucky with a smile on his face. When he blinks his eyes open, Steve’s lying on the couch watching him.

Watching them.

Even his eyes are smiling. He looks so fucking gorgeous. Bucky wants him to always look like this, always smell this vibrant with happiness.

“Morning, Sunshine,” Steve says, because Steve is an ass, and Bucky is anything but sunshine in the morning and they both know it.

Except for right now. This morning—if it’s even morning—Bucky thinks the name might be appropriate. Still, “You’re late,” is what he replies, because Steve was supposed to be his ride off the mountain and hadn’t shown up.

Steve’s smile dims. “Sorry,” he says. “Storm ruined the roads and none of us could reach you.” He glances at Stark and his guilt fades into something a little smug. “Worked out well though, didn’t it?”

Bucky strokes Stark’s back, the action somewhere between self-soothing and proprietary, and agrees, “Yeah. Our mate’s a fuckin’ force of nature, ain’t he?”

Steve’s answering smile is soft and awed. “He really is.”

“I’ve had such a crush on him, Stevie,” Bucky admits with trepidation.

To his relief, Steve’s smile widens. “Think some of mine rubbed off on you when I talked about him like a moonstruck idiot?”

Bucky grins back. “Maybe a little.” His expression wilts. “I think it’s me he didn’t want to know about being mates.”


“If we weren’t together he’d probably have told you. You could’a had him this whole time if it wasn’t for me.”

“You don’t know that. None of us…” Steve sighs. “Tony’s… Our relationship’s complicated.”

“Because of me.” Bucky makes himself say out loud what he’s known since Siberia. If Stark’s their mate, he can’t just pretend it’s not true anymore. “You don’t look as betrayed as he did when it’s just a friend, Steve. ’N falling out with a friend never broke you as hard as it did falling out with him. You knew what I did, and you protected me instead a’ tellin' him, and I know you. You wouldn’t a’ stepped out with him ’til you fessed up. You’re not together because of me.”

Steve’s scent sours, and old grief shadows his face. “I made some bad calls. Made some bad judgements—not just about you. He and I both did. But none of that’s your fault.”

Bucky wants to believe him, but can’t. “I killed his parents.” Stark’s face, Stark’s voice in that bunker—they haunt him. He has nightmares of killing people he killed, and killing people he didn’t, and of Stark and Steve in those moments, and things turning out far worse than they did.

They’re both his mates. Even more of his nightmares make sense now.

“You heard him,” Bucky says, “I killed his mom.”

“And six hours ago he flew halfway around the world and straight into a storm to save your life. He needed time to deal with it, and he’s had it. He would’ve had it by the time Zemo showed up if I’d told him when I found out you were alive. Things would’ve played out a lot different if Nat or I had said something. But we didn’t—and yet here we all are.”

Steve’s clearing scent makes Stark’s distressed scent more apparent, but the sub-vocal whine and the way he’s fidgeting against Bucky clenches it.

“Shit. Happy thoughts,” Bucky snaps, rubbing Stark’s back again and burying his nose in Stark’s hair to monitor his scent.

“I brought food,” Steve says in a rush. Then he huffs. “Enough for three of us.” He rolls his eyes.

Bucky lets himself be distracted. “JOCASTA?” he asks.


“Probably worried about her daddy.” Bucky knows he sounds a little fond, and lets his warm feelings about Stark fill his head. Steve’s told him what Stark’s like with his learning AIs, and he knows they’re just as fond of him. “You eat yet?”

“I’ll eat with you,” Steve says.

Bucky speaks fluent Steve. “That’s a ‘no,’” he says with evident disapproval.

“You’re probably starving.”

Bucky’s stomach makes its agreement known. Bucky wrinkles his nose and wills it to be quiet. He’s hot, and hungry, and wants to stretch, but this might be the only time Stark lets Bucky hold him, and he damned well wants it to last. “No more food talk,” he says. “Why ain’tcha kissed me yet, Stevie?” They have a rule about greeting each other with a kiss when they’re at home or among friends. “I’m kinda stuck. You need to come down here.”

Steve grumbles quietly, but all he smells like is happiness. He lays the couch cushions on the floor, hunkers down opposite Bucky and Tony, and kisses Bucky before settling down to share their pillow and very obviously scenting the air.

The scent of distressed omega finishes its progression into contented mate, and they grin at each other.

Now it’s perfect,” Bucky says as Steve and Stark’s scents twine in the air so close to his nose.

Steve strokes Bucky’s hair and curls his fingers in Stark’s and doesn’t say anything.

Neither of them does. They just color the room with the scent of contentment and happiness while Tony Stark sleeps.


Tony wakes up starving and too warm, but feeling amazing, which—weird.

Based on the three hands he feels touching him—one of them cloth-covered—and the heavenly scents mingled to perfection in his nose, Tony knows before he hacks into Steve’s phone for his location and sees the photo he messaged Tony and Barnes that both of his mates now know who he is.

And aren’t pissed, for some reason. The happy couple probably feels sorry for him—or grateful, ugh—and wants to be friends. Science save him from nice people. “Let’s be friends” is far from the optimal response, which would be a poly-exclusive relationship that would scandalize their 1940s sensibilities and thus is out of the question, and to be honest, them not knowing he existed was much preferable to explicitly being friend-zoned by your, for lack of a better term, soulmates.

It’s way too early to deal with this bullshit.

Actually, it’s 8:57pm on the same day he holed up in the cabin with Barnes. JOCASTA says Steve arrived with food for them all an hour and a half ago, and Barnes’s vitals say he’s been awake for most of that and is fully recovered. They also say he’s hungry and has been for hours. Just like Tony, who JOCASTA apparently went to great lengths to procure food for, and she wants him to know she’ll be quite hurt if he doesn’t stay to eat it. JOCASTA says Steve is hungry too. Her matchmaking attempts are not subtle. Tony tells her so.

This is fucking great. Everyone’s hungry, but these two Boy Scouts let him sleep. Fuck. At this rate he’ll be smelling their perfect scent on his armor for days and hating himself for loving it.

“If I didn’t know how you think I’d be concerned at how much your scent’s fluctuating right now,” Steve tells him, voice warm with amusement.

“This is normal?” Bucky asks, worry in his voice echoed by his scent.

“My brain believes at least seven impossible things before I open my eyes. You get used to it,” Tony deadpans, and opens said eyes. Best get this over with. He recalls the armor to its RT housing unit and tries not to wince when Barnes’s relief at being able to move is palpable. Barnes’s clothes are still damp, but Tony’s remain dry, if a little ripped and stained.

“It’s good to see you, Tony,” Steve says without looking at him. Tony’s in briefs and nothing else; Steve’s always been weird about modesty.

“Yeah, you too, Cap,” Tony says, pulling on his suit and shoes and attacking the buttons his kidnappers didn’t rip off moving him. When he turns back around, Barnes has a change of clothes in his hands and he and Steve are frowning at him, anger cloying the edges of their scents.

“I thought you were at a business meeting,” Steve says.

Tony shrugs and attaches the housing unit to his wrinkled white button-up. “Yeah, I was a little tied up with that, but I managed to get away in time to find Barnes and bring us here, so we’re good.”

“Bucky,” the man in question corrects on what looks like autopilot.

“Bucky then.” Tony nods and puts the couch between them on his way to the backpack full of food.

“There are rope marks on your clothes,” Steve says sharply. “And your suit is ripped.”

“Business hazard.”

“Someone kidnapped you.” Steve walks around the couch in two steps, and Tony has to force himself not to dodge the hands reaching for his wrists.

He doesn’t want anyone else knowing he’s essentially a super soldier now, so he shrugs and waits a few seconds before pulling away. “Relax. I’m fine now.”

If he couldn’t smell Bucky’s searing anger he’d have recognized it by the sound of him jerking on dry clothes. “How the fuck is that even possible?” Bucky growls. “You’re Iron Man.”

“Strategic use of copious drugs,” Tony says flippantly to hide how annoyed with himself he finally feels safe enough to be. “Why do you think I slept so hard?”

“Because you trust us to have your back.”

Oh Steve. God bless America. Even though most people think Steve is dead. “I do rest easier knowing you’re out there,” Tony says like he’s joking. He isn’t joking. He pulls out takeout containers and sets them on the table, then assesses the seating by the fireplace. The cabin’s cooling down already. And the table’s small. And none of its chairs are padded. Tony has needs.

“I sleep easier knowing you’re out there too,” Steve says, and his sincerity makes Tony’s heart skip in a way that makes him paranoid his heart condition’s back even though Extremis regrew all his organs in super human condition and with far greater durability. “We both do.” 

“There it is, ladies and gentlemen,” Tony says, hoisting the camping backpack to the couch, “the sincerity that launched a thousand ships.”

Steve snorts, and Barnes—Bucky—laughs. It lights up his eyes and his whole face, and Tony sees the ladykiller he was when he was younger in that gorgeous smile.

Goddamn heart condition. His mates will be the death of him just by existing.

He tells himself to get a grip. “Bucky, fix the fire, it’s fucking freezing and your left hand doesn’t get splinters. Steve, fix the couch, I know you’re the reason it’s naked. Jo, tell me who gets what.”

Tony hunkers down on the blankets he and Bucky discarded and pretends he’s not surprised, much less pleased, that Bucky and Steve, quintessential alphas, just…do what he tells them. He’s so busy pretending, he doesn’t realize JOCASTA, the traitor, has been directing the food sorting entirely in Tony’s head until he’s made three neat stacks of cartons and tubs and water bottles, and asks Steve what he’s doing sitting in front of Bucky’s.

“They couldn’t hear your conversation, boss,” FRIDAY lilts from the speaker of Tony’s recovered phone.

“How is that possible?” Steve asks. “We both have enhanced hearing.”

Bucky sits across from him looking delighted. “The same way he hacked the power grid and scrubbed the internet—”

No,” Steve says immediately.

“—and always knows where to find us!”

“Don’t start this again.”

Bucky stabs his fork at Steve. “You owe me a blowjob and two weeks of dishes!”

Tony gapes at them. “What?”

Steve looks incredulous. “I do not, because you are wrong!

“Our mate’s a fucking technomancer,” Bucky crows triumphantly.

“Buck, there’s no such thing as a—”

“Holy shit,” Tony breathes as he realizes, “I am a technomancer.” He laughs into his soup.

Steve casts him a beleaguered look. “Please don’t encourage him.”

Steve’s phone chimes with an incoming message. “Gonna check that?” Tony asks, and spoons a matzoh ball into his mouth.

“Could be Sharon,” Bucky says, suddenly all business. He puts his sandwich down and pulls out his own phone, which he’s powering with a charger Steve pulled from his backpack.

Tony watches them read his text message in the group chat he just set up with a gleeful smirk: Steve, tell me about the blowjob you officially owe Bucky.

Steve’s mouth falls open and he turns red all the way down to his neck, before his head thumps into his free hand and starts shaking back and forth.

Bucky laughs even harder than he did at Tony’s Helen of Troy joke.

Tony buzzes with contentment watching them.

“This is my fault,” Steve moans, scrubbing his hand down over his mouth and then off his face. “I picked them and the universe backed my play. This pain is my fault.”

“You always did like sexy brunets that’re smarter ’n you,” Bucky drawls, still tittering, in a ‘40s Brooklyn accent that does things to Tony’s insides.

“Yeah, laugh it up now—your turn’s coming.” Steve’s testy tone is at odds with his scent: happy through and through.

Tony banters with them all through dinner and it’s surprisingly not awkward—it’s like hanging out with Steve at the Tower used to be, but better, because they each draw out sides of one another that the other person finds new and intriguing. It all feels surprisingly easy, right through the last bite from the last unempty container, and then on past it. Easy enough that Tony mostly doesn’t notice how closely Steve’s studying him until he’s caught the phone Steve hurled with super speed right at his face.

All three of them stop. Steve’s lips quirk ruefully. “You’re not just a technomancer, are you, Tony?”

Which he clearly already knows. Tony glares at him and viciously chucks the phone back. Steve’s eyes widen when he catches it, like his hand hurts, and Tony feels slightly mollified. “What gave me away?”

Steve’s eyes drop momentarily to Tony’s chest. “All your scars are gone. Every single one. So are your freckles, and some of the gold flecks in your eyes. The callouses on your fingers are thinner. Your sock has blood on it under a knife cut in your slacks, but there’s no corresponding wound. When I reached for your hands to check for rope burn, you started pulling away just as fast, and then you panicked, made the same split second calculation I’ve watched you make a thousand times, and kept your hands right where they were to let me take them.”

There’s a reason Steve’s in charge on the battlefield instead of Tony, and if Tony weren’t so annoyed, Steve’s Sherlock act would get him hot like it usually does. “You could go on, couldn’t you.” It isn’t a question.

Steve grins. “Of course. That was the short list.”

He’s all sass now. Imaginary-god save Tony before he jumps this unfairly sexy man. He pretends to ignore the spicy scent of Bucky’s lust, and the banked heat in Steve’s eyes when he glances at Bucky and abruptly ducks his head like he’s shy before turning his gaze back to Tony—who very manfully doesn’t think about how much he wants to jump both of them right now.

Steve helps by putting on his cheesy Captain America For Kids face and jutting a fist on his hip, the spitting image of his high school PSA persona, the videos of which Peter pretends to hate but has saved in a secret Avengers fanboy folder on his laptop. “So, Tony,” Captain America says, “tell me about all the strange and exciting new changes your body’s been going through since the un-Snap.”

Tony wants to shove him away in disgust, and also laugh so hard he falls over. Instead he clears his throat and does what Steve asked. “It’s no big deal. I’m a little faster, little more durable. Maya’s weaponized version of Extremis was designed as a next-level super soldier serum, based on yours but with crazy shit like breathing fire, among other things—one man army, three-man crew can storm the gates and take down a government without breaking a sweat kinda deal. Those never went to human trials, thank fuck. The limb-regrowth strain for civilians was dangerous enough—human trials literally explosive. Removed that from Pepper years before I thought some work might get Extremis to do what I needed. So I took the military version, streamlined and stabilized it, spent a full day screaming and wishing I was dead while my body ripped itself apart on a molecular level and rebuilt from the ground up, and now I’m a technomancer and can probably keep up with you.” He winks. “Like I said: no big deal.”

“Did you test it on anything first?” Steve asks, incredulous, because of course he’s worried about safety instead of being appropriately awed that Tony literally evolved himself into a higher life form.

“That is so fuckin’ cool,” Bucky says, lust deepening in his scent.

“Thank you. That is the appropriate response,” Tony says, motioning at Bucky like he’s Vanna White. Tony has a hunch Bucky’s as sapiosexual as he is. Not that Tony’ll ever get to explore that, no matter what Bucky’s scent says, because 1940s sensibilities don’t include threesomes.

“You could have died,” Steve sputters.

“Oh, please. I’m obviously fine. I was careful, Steve, jeez.”

“Careful like your initial Iron Man trials?”

Tony shoves a finger at him. “Vision had no right to show you those videos.”

You could have died,” Steve repeats, like it’s somehow more relevant now than fifteen seconds ago.

“But I didn’t! I’m fine!”

And right that minute Tony’s reminded Steve’s not just Steve anymore, he’s an alpha, because Tony watches the protective instincts kick in harder than they ever did before the Snap, and he’s so stunned he lets Steve get between him and the couch and manhandle him into leaning back against Steve’s chest and being the little spoon in a vice grip that Tony could technically break free of now, but only because he’s enhanced.

Steve’s apologizing even as he presses his nose into Tony’s neck and inhales audibly.

“It’s fine, I get it,” Tony says, because he does. The first time he pulled Bucky and Steve out of the proverbial and literal fire, they’d passed out from smoke inhalation, and Tony scent marked their necks like a creep the minute he got them safely to an empty apartment a few blocks away. He pats Steve’s hand awkwardly and waits for the panic in his scent to go down. He doesn’t want you, Tony reminds himself, He’s a close friend, and you scared him the same way you scared Pepper when she found out what you did. It doesn’t mean anything more than that. No matter how much you want it to.

Bucky sighs and hops over like a capoeira master, unfairly graceful and clever, and leans against Steve’s side. He hooks his right arm around Steve’s, wrapped around Tony, and his scent mingles with theirs and Tony relaxes, and feels Steve relaxing too. “We should probably have the mate talk where we ask you to join our relationship and you give a bunch of bullshit reasons why you won’t instead of saying the one that matters so we can shoot it down,” Bucky says, quite unfairly.

Unfairly accurately.

Steve must’ve snitched while Tony was sleeping, since it sounds like they’ve discussed it already.

Tony huffs. “What makes you think I’d say no?” he says to be contrary; he hates that even Barnes knows his M.O. 

“You sayin’ yes then?” Bucky asks, chin propped on Tony’s shoulder so he can’t see either of their faces.

“I didn’t say that.”

“You didn’t want us to know you were ours, and you ain’t sayin’ yes to being our fella, and I know you’re too smart not to have a good reason, so I wanna know what it is.” Bucky pauses. Sadness sours his scent. “I got a theory… And it’s fine. We can have an arrangement, folks do that these days. I just wanna know I’m right.”

“That’s not why,” Steve whispers, so sweetly, and twines his fingers through Bucky’s against Tony’s chest.

Blaming a fake weak heart for the sudden pain the gesture, scent, intimacy pierces through his chest, is easier than acknowledging his own feelings. Omegas are supposed to be all about feelings and nurturing, neither of which fits Tony because, even evolved, he’s apparently still defective.

Howard would be so proud.

Steve scent-marks him.

Runs his face along not just one, but both sides of Tony’s neck, and all around the back in between.

Tony instantly feels better—even though Steve should’ve asked his permission first, consent is sexy, honestly. But since Bucky packs a battery of chastisement into both syllables of “Steven,“ Tony considers his honor properly defended.

“Sorry,” Steve mumbles.

Tony shakes his head in lieu of reply.

Bucky takes an audible breath. “If you woke up and it was just you ’n me, and you knew I was fine, and that Stevie was comin’, would you’ve left again without tellin’ us it was you?”

When Tony doesn’t speak for long moments, Steve says, “Tony,” and it’s too much. He caves.

He feels uncomfortably like an echo of Steve’s in that motherfucking bunker when he shamefully breathes out, “Yes.”

Steve pulls him closer. Bucky, conversely, moves his face away, back toward the couch, closer to Steve, like he’s trying to close ranks and Tony’s not part of them.

Expecting it doesn’t make it hurt any less.

“Why?” Bucky asks, voice resigned, like he already knows the answer.

His scent is sour, the air around them is starting to smell like misery, and Tony aches to fix it. Fucking omega hormones. Tony’s not signing up to be a third wheel in their perfect relationship. They don’t need him to be happy—they never did and god does he know it. It was better before he glimpsed what he’s been missing, but he’s not the Avenger with a time turner, so he’ll just have to suck it up.

“You know, Barnes, you’re lucky,” Tony says. He pretends he doesn’t feel Bucky flinch.

No: Barnes.

Shit. No: Bucky. Bucky, whose vital signs are registering chest pains because the human brain is an asshole that sets off nerves in response to emotional injuries too.

“Bucky,” Tony corrects himself with a sigh. He folds himself around his raised knees and turns sideways to watch Bucky’s face. He can’t look at Steve for this. “Sergeant James Buchanan Barnes. You think you’re the problem, right? Killed my parents, I only put up with you ‘cause I care about Steve too much to let you die? Something like that?”

Bucky nods, the barest of movements, but it’s enough.

He looks so painfully young Tony reaches for him before he can think not to. Strokes Bucky’s pretty hair and moves down to cup his tense jaw. He’s relieved at least he can fix this misapprehension. “All of that’s bullshit. I know why my parents died—you’re just one piece in a thousand-piece puzzle of cause and effect, honey, and no one who knows the truth holds you responsible for that night.” He grins ruefully. “I actually think you’re pretty great. Pepper says that proves I’m a good person, but she not objective so the jury’s still out. Whatever. Point is, you are a good person, and I like you so much it makes me feel like a creep sometimes. You’re not the problem.” Tony pulls his hand back, curls it over his knee and rests his head on his arm. “The problem’s me and Steve.”

Tony feels like an asshole for ripping the hope right back off Bucky’s face.

Steve is so still around him Tony can barely hear him breathe.

He tries not to think about the spike of misery in Steve’s scent. Tries not to smell anything, or feel anything. “You know Steve Rogers’s best friend Bucky Barnes is the only thing in the world he chose to keep? He killed Captain America and the Avengers for you. He beat Thanos for you. He’d burn down the world for you if he had to. And he’d go through me to do it—every time. Maybe next time he’ll hesitate, but he’ll still do it.” Tony looks at the three empty stacks of takeout, then fixes his eyes on the door he’ll be walking out of alone soon enough. It’s easier than looking at his mates.

He finds himself smoothing down the hair on his forearm with his thumb, a self-soothing gesture, every stroke in the same direction.

If Bucky’s face had looked that stricken, he’s afraid to even glimpse Steve’s when he finishes: “I can’t put myself in an equation with either of you and expect it to balance out. It may look like the three of us, but when things get rough, it’ll always come down to the two of you on one side and me on the other. That’s a fucked up way to be mates. I can’t—I can’t do that. Don’t ask me to do that.” Because I will, he doesn’t say.

Steve’s hands are lax against him. The scent of his misery and their combined disappointment feels like it’s drowning him. He’s disappointed his alphas—both of them. His designation is clawing at him to fix it, make them happy, submit, do anything. But Tony’s always looking to the future, and the writing’s been on the wall for years.

Except then Steve’s scent clears. “That’s your whole reason? Nothing to add?”

“Not at the moment,” Tony says, mentally prying himself off the edge. Because—goddammit—Steve’s gearing up for a fight. An argument. Whatever—he’s not letting Tony vanish, Tony knows that for sure, because that’s the same tone Steve’s used to launch countless debates with him already.

Steve folds his legs around Tony, hemming him in with all four limbs. His eyes narrow. “You think I’d burn down the world for Bucky, but not for you.”

“It’s happened before.”

“Alright. First: that’s not true. There’s nothing I’ve done for Bucky that I wouldn’t do for you in a similar situation. If the police were hunting you down with a kill order for a crime you didn’t commit I’d fight them to protect you too.”

“Leipzig airport. You abandoned your team to save him.”

“Bucky knew that Hydra base—I needed him to get in. He’s the only one we couldn’t afford to lose if we were going to beat Zemo to those other Winter Soldiers.”

“You split up the Avengers.”

“No, the Accords split up the Avengers. They had no right to ask us to sign.”

Tony wants to throttle him. “One hundred and seventeen countries asked for oversight—”

“There’s oversight and there’s signing your life away,” Steve says, limbs tightening around him. “They wanted my DNA on file, Tony. Do you know how many super soldier serum knockoffs would be out there if anyone could access a write-up of my DNA—and any number of other enhanced’s DNA—just by hacking a database? How many times would they have come back to me for blood because their samples ‘disappeared’ when they sold them to the next highest bidder on the list? I read the terms—the Accords were dangerous and it would’ve been irresponsible to sign them.”

“Okay, that’s fair,” Tony concedes, because it’s nothing he hasn’t already thought and rectified, “Ross’s version was kind of Big Brother—but we’ve pushed through a lot of changes, enough that you’d sign them now, I think. They’re reasonable terms now.” Tony wouldn’t let Peter anywhere near the Accords if they weren’t.  

“I believe you,” Steve says. “I probably would. If we’d had time to make changes before their sign-or-retire ultimatum, Leipzig never would’ve happened. You and I disagree, but we always come to an understanding if we have time to hash things out. We’ve only ever fought when we were on someone else’s countdown. Leipzig and the Accords were on Ross’s, and we didn’t have time to explain at the airport because you were on a time crunch to bring us in before they sent in the military.”

“We’ve fought on our own timetables too.”

Steve looks preemptively smug, the asshole. “Name one time that happened.”

“Siberia,” Tony says flatly.

“Zemo’s timetable.” Steve raises an eyebrow.

Tony’s eyes narrow. “Making Vision.”

“You had three minutes to get his body up and running before it was no longer viable. No time to talk.”

“On the helicarrier, before Loki escaped. We nearly threw down.”

“We all did, but only in the room with the scepter. Everywhere else we got along fine.”

Tony fumes and pretends he’s not starting to have fun, because sue him, debating Steve is fun. He thinks Steve might be right on this one, but can’t stop grasping at straws. “Almost half our movie nights.” Shit. Bad move, but it’s too late to take back.

Steve has the gall to laugh. “You saw what Nat did to Clint when he took too long to pick a movie—what was it, night three? We were all on Nat’s timetable.”

“And Darcy’s,” Tony adds even though it pokes holes in his argument.

He and Steve share a traumatized look, remembering.

“Tony, I have never ‘gone through’ you unless we were out of time and lives were at stake—and each of those times you would’ve gone through me right back. But you and I always work things out unless someone forces our hand,” Steve says firmly. “I don’t see that changing.”

“You gave up the shield for him,” Tony tries next.

“I gave up the title for the Accords, not the job; and I gave up the shield because you didn’t want me to have it. You said I didn’t deserve it after what I did, and you were probably right.”

And how many nights since then had Tony worried about Steve off covertly Avenging without the only thing that kept him bulletproof? “I was being petty. You should’ve told me to fuck off and kept it on you.”

“I hurt you more than enough that day without doing that.”

“And I tried to murder an innocent man and was willing to break you in half to do it. It wasn’t a good look, you shouldn’t’ve encouraged it.”

Steve’s expression softens further. “You were worried about me.”

“You left me your bulletproof shield and kept your propensity for sprinting face first into gunfire. Of course I was worried.”

Bucky snorts. When Tony glances at him, he rolls his eyes and glares pointedly at Steve. Tony can one hundred percent relate.

“Whatever. Third wheel isn’t a good look for me either,” Tony says. “You’ve got decades of history that I don’t.”

“So you think I’m going to play favorites. We’re inviting you to play a rigged game.”

Tony hesitates. He’s pretty sure Steve’s about to shoot that down.

“I don’t want to be unfair to anyone,” Steve says. “You have blanket permission to punch me if I am.”

Tony suddenly feels cold, itches to move as if it will distance him from the memory of the day he actually punched Steve in his perfect teeth. Steve’s wounds at his armored hands still haunt him, and thanks to Extremis, he could probably do the same damage without armor now. “Mate abuse, that’s your solution? If being punched made people smarter, you’d be a genius. Let go of me.”

Steve sighs and releases Tony, but Bucky lays a soothing hand on Tony’s arm before he can get up, and snares him with his gaze. “He’s not asking you to hurt him,” Bucky says earnestly. “It’s just, his first response when he sees a bully is to call ‘em out and punch ‘em ’til they act right. He’s always been like that, even when he was too small to land a punch without hurting himself worse than the other guy.”

“I wasn’t that bad,” Steve says, frowning at Bucky.

“He was like a chihuahua goin’ for a Great Dane every single time,” Bucky tells Tony wryly. “I got good at boxing real quick to make sure he didn’t get us killed in an alley somewhere.”

“It wasn’t like that,” Steve says. “And you started boxing to impress—what was her name, Mary? Mary Connors?”

Bucky rolls his eyes. “I had to tell you something.”

Steve huffs. “Remind me to punch you when we get home.”

“You’re a hundred-year-old man with a death certificate,” Bucky drawls, eyes gleaming with challenge. “You couldn’t catch me long enough to swing.”

Tony snorts, amused as their bickering continues, and is soothed despite himself by their sweetening scents. Clint called Tony and Steve razzing each other The Steve and Tony Show. If it’s anything like The Steve and Bucky Show playing out in front of him, he understands why Clint liked to start friendly arguments to watch him and Steve duke it out.

Damn—Tony misses The Steve and Tony Show so much it hurts sometimes.

“Look, Tony,” Bucky says kindly, when Tony thinks they’ve forgotten he’s even there, “you’re looking at this the wrong way.”

Tony purses his lips. “Enlighten me.”

“We’ve all done unforgivable things to each other—we’ve nearly killed each other—and yet we all still want this relationship, and we’ve done stupid things to take care of each other even thinking we couldn’t have it. Do you honestly think things’ll get worse for us than Siberia? Or Project Insight?” he adds, looking at Steve. ”You’re a genius, Tony. What are the odds against us if we all got here from that? We’re mates because the universe knows we’ll be good together. The deck’s stacked in our favor. You’re just saying no because you’re scared.”

Tony was with him up until that point. “I am not scared.”

“You are,” Steve says, amusement rudely evident. He cocks his head at Bucky. “Can you believe it? The same Tony Stark that attacked Thanos on fourteen-million-to-one odds and brought a wristwatch to a gunfight with the Winter Soldier isn’t brave enough to be our fella.”

“Looks that way,” Bucky agrees. “Can’t tell if I should be flattered, or embarrassed for him.”

“I know what you’re doing,” Tony snaps, unimpressed.

“I’d be worried if you didn’t,” Steve says, good humor still evident in the tilt of his lips.

“This is gonna blow up in our faces,” Tony says.

“Then we’ll rebuild it even better.”

Tony raises an eyebrow at him. “Together?” he says wryly.

Steve closes a warm hand around Tony’s ankle. “Together,” he says, and his resolve inspires an answering determination and hope in Tony’s chest just like it always does. ”On or off the battlefield, the two of us have always been better together. Tony, just think what the three of us could do.”

Tony sighs. He’s lost an argument he wanted to lose and gained a relationship he wanted but thought he couldn’t have. No reason to draw things out any longer. “Fine, you win,” he tells Steve, flippancy cloaking his nerves, “but I get Bucky in the divorce.”

Steve’s mouth drops open. He’s still sputtering, “Divorce?!” when Tony finds himself with an armful of laughing Bucky and a nose-full of happy alpha.

“Thank you,” Bucky tells him. “You won’t regret this.”

Steve slumps around them both, and with unsuccessfully quelled happiness and hope, Tony breathes in his two mates, who he is now dating even though he’s sure they’re going to be the death of him.

“Why do you get Bucky?” Steve grumbles into Tony’s neck.

Tony shrugs, but lightly enough not to discourage them from holding him. “You got him last time.”

After a pause, Steve admits, “That would be fair.”

“There will be no divorcing in this house,” Bucky admonishes.

“Yes, dear,” Tony and Steve say in unison. It sets off a round of laughter that clears the last wisps of unhappy scent from the cozy room.

Later the three of them will scent mark each other—with permission—for the first time. Later they will share first kisses, and clean up the cabin, and drive back down the mountain together. And later they will go on dates, and Tony will discover 1940s sensibilities leave plenty of room for threesomes, and that being two alphas and an omega adds surprisingly pleasurable new elements to Tony’s considerable sexual repertoire. Still later Tony will discover they can fight and he won’t be left standing alone, and the relationship won’t blow up in their faces; and something will settle inside him at long last, because even as they’re fighting, Steve and Bucky keep on kissing him in greeting, and anger obviously doesn’t make them love him any less.

But that’s later.

Now they hold onto each other, and the cabin slowly fills with the fresh scent of their elation.