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A Fire to be Kindled

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Tony doesn’t notice it at first. He’s still remembering “It seems to run on some form of electricity!”, has labeled Steve as an old-fashioned good guy without a good grasp on science and then promptly written that part of him off – except for the occasional joke. To be fair, that’s not all his fault – he’s Tony Stark, he has important people to do and things to see, he can’t spend all his time speculating about his new team mates.

Then, Steve and the rest of the Avengers slowly take residence around him, and Tony still doesn’t notice. Okay, so he has to eat that remark about Steve being confounded by electricity when Steve proceed to use his (unnecessarily complicated – it amuses Tony to see people fail) microwave with ease, but he still doesn’t notice. Not until he and Bruce are discussing a hypothetical physics question Tony stumbled over online and Steve helpfully chips in about how, the last time he checked, they had to take relative rotation into account for that to work.

Bruce is left explaining to Steve that their scenario is happening in a hypothetical reality while Tony gapes, because no one told him the serum gave Steve brains as well. (The trouble he was in before is nothing compared to this.)

*

It makes perfect sense, of course. The serum gave Steve the perfect body, so why wouldn’t it also give him the perfect mind? In the quietness of his own mind, Tony can admit he’s a little stung Steve didn’t tell him, but he’s not really surprised.

Steve doesn’t think it’s a big deal at all. “I learn faster,” he says with a shrug when Tony finally asks him about it, “It’s come in useful a few times.”

“I’ll bet you it has,” Tony says. He immediately thinks of German and quick thinking behind enemy lines – he’s not sure whether it’s Steve or himself who doesn’t let Steve lose the persona of a soldier. “How does it feel?”

“Faster,” Steve repeats with an amused curve to his lips. “Everything makes sense faster.”

“Interesting,” Tony hums. It does explain Steve’s relative ease, adjusting to the 21st century – Tony has been quietly impressed by how well he’s doing, and he’s not the only one. Steve maneuvers cell phones and computers much better than first assumed, and Tony spent a good few hours lamenting how he can’t teach Steve technology if he already knows it. (He had some choice ulterior motives in mind, of course, but that’s nothing new.)

*

A few days later, Tony gives the SHIELD and the rest of the team a debriefing on his and Bruce’s recent discovery, a stretchy pair of pants they’ve all been awaiting. Seriously, if Tony had a dime for every time he’s been inadvertently flashed Hulk-junk, he’d be rich twice over. He gives them all the Simple English version for the benefit of all save Bruce – and, if he reads the light in Steve’s eyes correctly, Steve.

He’s right – Steve finds him later, looking shy but determined in that unique way of his. “What would I have to read to understand the long version?”

“You want to learn to make Hulk-pants? Really?” Tony asks with raised eyebrows. “Well, Cap, I wasn’t going to say anything, but you have been coming down pretty hard on Bruce’s cupcakes lately.”

“Shut it,” Steve says. He’s not quite smiling, but he’s stopped reading malice behind Tony’s joking barbs – it’s a step in the right direction. “I’m serious.”

“Well, that could – and has – filled a library,” Tony says. “Hold on, though, I’ll cough up some books for you.”

*

Steve returns the books two days later. Tony doesn’t bother hiding his surprise. “Not for you?” he asks, absurdly disappointed.

“No, I finished them,” Steve says, looking embarrassed. “They were— they were easy.” He says it like it’s a secret, like it’s something vaguely shameful, and Tony thinks, oh.

Steve has never been dumb, was probably too smart for his own good even before the serum, and he’s registered the changes the serum’s had on his cognitive abilities – but he hasn’t been brilliant before, not like this, and his limits have yet to be re-defined.

Tony’s lips stretch into a smile. “Feels new, huh, Cap? Tell you what—” he takes the books out of Steve’s hands and puts them in the trash, the only reason he got dead-tree versions in the first place was because of Steve, “—I’ll explain this stuff to you, ‘kay? That’ll go faster.”

“You—” Steve blinks. “You’d do that? Really? You aren’t too busy?” He looks around the workshop, lit up like a Christmas tree with projects.

Tony huffs, and clears the holograms off his workspace with a wave. “Too busy to teach Captain America physics? Never.

Steve smiles.

*

None of the Avengers sleep much. Their reasons vary – Bruce is used to waking at the slightest footsteps, ready to escape out the back door and into the night. Steve doesn’t need to sleep much, a side-effect of the serum; Natasha and Clint are seasoned SHIELD agents, and Thor enters this occasional hibernation stage. Tony’s never slept much, has to exhaust his brain before he can rest properly, so altogether, they usually average out at four or five hours a night.

Still, night-time is one of the few sacred things in the Tower. Despite everybody knowing that everybody else is awake, they don’t have to deal with them, or even consider their existence. In a Tower mostly filled with explosive personalities, this time is sorely needed. It’s the only time Tony ever feels like he’s living alone again. The entire place is quiet, the common areas empty, and he tells himself it’s a breath of fresh air (except when it really isn’t, and JARVIS has to do a head count for him).

In other words, Tony is surprised to find Natasha and Steve in the kitchen when he’s up to get more coffee beans at one AM. They’re eating dip, neat rows of sliced carrots and celery on the table between them. Natasha neatly dips a carrot and eats it in small bites while Steve talks, her lips curled in a small, intimate smile.

Tony blinks. “Uh,” he says, “hey, guys.”

“Hi, Tony,” Steve says, pausing. “You joining us?”

“Dunno,” Tony says, rooting in the cupboard for the bag of Italian roast he swears he saw here last week. He hopes it didn’t fall victim to Barton’s weird habit of eating coffee grounds. “What’re you talking about?”

“Steve’s telling me about his superior officers during the war,” Natasha says, after the sharp crack of a celery stick. “They were quite the figures.”

“I’m sure,” Tony says, stealing a carrot and a large helping of dip. “Oh, hey, Steve, I was meaning to ask you, how’s the new reading going?”

“It’s going well! It’s very interesting,” Steve says. He glances over Natasha, who gave him a relenting shrug, and refocuses on Tony. “I actually had something to ask you.”

“Yeah?” Tony asks, taking another carrot.

“How do physicists justify superheroes?” Steve asks. “I assume it’s not just blaming it all on magic.”

“Fucking magic,” Tony says darkly, before perking up again. “Well, they work with a ‘miracle exception’, which, short version, is magic, and from there they just apply the laws—” As Tony explains and Steve listens avidly, neither of them give Natasha proper notice when she leaves – even though she takes the dip with her.

*

They spend a couple of weeks going over the basics, building Steve’s fundament. Smart or not, the guy still slept through some damn important scientific breakthroughs, and what with a war on, he didn’t exactly have time to read much before getting iced.

They usually dump down on one of the couches in Tony’s workshop, Tony commanding holograms to illustrate his point. This teaching gig actually doesn’t seem so bad, even though Tony was mainly thinking of it in lines of, get to spend more time with Steve and less, watching Iron Man’s paint dry is literally more interesting than waiting for people to understand stuff when he proposed it. Luckily, Steve gets it faster than Tony was afraid of, and some of his questions are refreshing or even downright interesting.

Thinking about it, he still wouldn’t touch school kids with a ten foot pole, though.

*

The autumn wind blows cold against Tony’s cheeks. He grumbles, wishing he’d brought a scarf – better yet, driven. The walking was Steve’s idea, and the others had quickly agreed, leaving Tony the sole protester. In a dictatorship, he thinks viciously, there’s no such thing as five against one.

He’d debating the pros and cons of a Starktatorship when Steve falls back from the front to walk beside him, smiling slightly. “You okay back here?”

Tony sniffs. “I’m great,” he says, “just wishing for a warmed car instead of this.” He gestures to the windy street around them, bedecked with red and yellow leaves.

“This isn’t cold,” Steve says. He says it good-naturedly, but Tony still feels a ridiculous flash of guilt that he’s quick to brush off. “Besides, red and gold – isn’t that your colors?”

“Right,” Tony deadpans. “Iron Man’s stuck in a permanent fall collection.”

Steve laughs a little. “You could add a Christmas hat to the helmet once December rolls around.”

“I’d have to glue it on,” Tony muses. “Wouldn’t do to have it fall of during a dramatic showdown with Doom, or someone.”

“Or you could do a chinstrap solution,” Steve suggests. “Like a party hat?”

Tony bursts out laughing at the mental image, and Steve looks pleased. “What’s this exhibition for, anyway?” Tony asks, after they’ve walked down another street. He tends to zone out when he’s addressed as a member of a group.

“Oh, emission theory,” Steve says. “I was just going to ask you and Bruce whether you wanted to come, but the others were there when I asked, and they didn’t want to miss out.”

“They wouldn’t have,” Tony told him. “Emission theory is pretty much disproven, only a few people hold to it nowadays.”

“Really?” Steve asks, crestfallen. “Bruce didn’t mention that.”

“He probably didn’t want to hurt your feelings,” Tony says. “Anyway, it doesn’t matter much. It’s still very interesting.”

Steve side-eyes Tony for a beat, then says, “You think it’s boring as hell, don’t you.”

“... yeah,” Tony admits.

“Damn,” Steve says, slumping a bit, and Tony grins.

“Don’t worry about it, we’re almost there anyway. And seeing Thor trying to blend in with people on the street will never not be funny, so it’s worth it just for that. Trust me.”

“Okay,” Steve says. He looks like he might say more, but Bruce falls in step beside Tony, and all three of them talk the rest of the way.

*

“The point is that you should’ve seen it, Clint,” Steve roars. He’s angry. Clint sits by the table, resting his knee, practically vibrating with tension. “It was a stupid, foolhardy risk and you should’ve seen that it wouldn’t work!”

They’ve just arrived back from a run-in with Amora the Enchantress – and Tony doesn’t mind hot alien women, but he feels like a large proportion of the Asgardian population is batshit and/or evil, they should probably revise their parenting ways – and gotten by with a few scrapes each, except Clint, who had to jump off a building to get proper aim (one-trick pony much, Tony thinks) and was hoping the grey substance Amora had conjured would catch his fall.

Spoiler: it didn’t.

Clint doesn’t say anything, and neither do any of the other Avengers. Steve rarely loses his temperament like this, tends to be one of the more practical and level-headed of them. Tony’s only seen it a few times before, in all the months he’s known Steve.

“It looked like it would work,” Clint says finally, his voice rough and tense, and he shakes off Natasha’s hand as she lays it on his shoulder. “And fuck you, Cap.”

Bruce and Thor are both absent, but Natasha and Tony are standing around the two, watching. Tony feels like he should step in, somehow, but he’s never been good at calming people down – it’s the firing people up part he’s got down pat. He stares at Natasha, imploring her to do something before Clint gets worse fucked up, but she is busy looking between Steve and Clint.

Steve takes a step forward, and Tony shoots a hand out to stop him. He’s still in the armor, which is the only reason he can keep Steve from moving. Steve looks at Tony, who has his faceplate up, then deflates a little. “It didn’t look like that at all,” he says, and he sounds almost confused, unintended condescension coloring his tone.

“Well, gee-whiz,” Clint snarls, “I’m sorry we can’t all do highly complicated density math while in the middle of a fight, we’re not all brilliant superhumans.” He gets up, and has to contain a full-body shudder at the movement – determined, he limps out the door. Natasha gives both Steve and Tony a look, and follows him.

Tony takes off his helmet with a sigh, and Steve takes it as an accusation. “I’m not wrong,” he says, “it was a stupid move, and he shouldn’t have done it.”

“I agree,” Tony says, “but Cap, you can’t tell him like that. Look, I know you’re not used to this, but you have to remember that you operate on a different level than most people.”

“Clint’s not stupid,” Steve says immediately. His loyalty and faith in other people still astounds Tony sometimes - how he could yell at Clint like that and then stick up for him the next minute. Or maybe Steve’s just terrible at holding a grudge. “He calculates trajectory, and—”

“He’s specialized in that,” Tony cuts in. He takes Clint’s seat, and gestures for Steve to sit down. Getting out of the armor can wait a little. “Clint’s not stupid, but he’s been shooting with a bow and arrow for so long it’s second nature to him now. It’s not really a good thing to compare it to.”

“But it was so obvious” Steve says, lost, sitting down. Tony is reminded of shouting at his parents, his tutors, his maids, no, no, no! That’s wrong, that’s so obviously wrong, you’re doing everything wrong! Why can’t you just see what I see?

“To you,” is all he says. “Remember that.” They sit there in silence, until more of the tension bleeds away from Steve’s posture - he was, at the bottom of it, worried about Clint (they all were, Tony had his heart in his throat as he watched him fall). “Are you okay?” he asks, finally.

“Yeah, I just,” Steve says, reaches up to rub at his temples. “All of this gave me a headache.”

“Hmm,” Tony says – he didn’t know Steve could get headaches. “I’ve gotta get out of the armor,” he says, and Steve says, “Oh, right, yeah, okay.”

Tony raises his eyebrows, but Steve just takes a breath and gives him a nod, so Tony grabs his helmet and heads down to the workshop. There are some tunings he want done, and Amora’s yucky grey substance got into one of his boots and a knee joint – he has some theories about how to optimize joint movement without losing protection, so it’s just as well he has to redo it.

*

“And that is how you make a steel-titanium alloy,” Tony says.

Steve inspects the bit of metal in his hands. “Not as thrilling as I was expecting,” he finally concluded. “Unpainted it looks like anything else.”

Tony snorts. “It’s a damn cool alloy, but it’s still metal,” he says. “What were you expecting? A free blowjob and the secrets of the universe?”

Steve shrugs. “Maybe a little,” he grudgingly admits, having long grown used to Tony’s casually crude language. “I—” He looks up at the ceiling. “Hey, how’d you make JARVIS?”

“A lot of alcohol and a lot of desperation,” Tony says bluntly. “Also, he took me a year and a half – really, you guys don’t seem to realize how incredibly complex and ahead of his time he is. Let’s just say it’s a good thing I invented a new power source, okay – he needs a lot of it.”

“Oh,” Steve says. His eyes have an admiring shine in them that Tony’s liking way too much. “Your other robots, are they as—” he hesitates.

“Smart? Amazing? Capable?” Tony bursts out laughing. “Oh, my God, no. Jesus, Dum-E, U and Butterfingers are so far from JARVIS’s league it’s in bad taste to compare them. It’s like – it’s like comparing a bed-ridden five year old to Thor, okay.”

“Thank you, sir.”

“No problem, baby.” Tony turns back to Steve, who has that quirk on his brow. “Yeah?”

“Can you teach me that?”

“Programming? Really? It’s a whole other bucket of fish than what we’ve been working with so far.”

“I know,” Steve says. “I just— I want to know more about this century, and I want to—” belong, he doesn’t say, but Tony’s pretty good at filling in blanks. Besides, he knows the feeling all too well.

Tony looks around, and hands Steve a laptop lying nearby, grabbing a tablet for himself. “Okay, then. Let’s hope you take to this as easy as you’ve done the other stuff, or this could be a rocky road.”

*

“Friend Tony!” Thor says, with a clap to his back that makes Tony stumble. “I am glad to see you are still among the living.”

“Ha ha,” Tony says, grabbing an orange juice from the fridge and drinking straight from the carton. Natasha makes a noise of disapproval from where she’s sitting by the kitchen table, solving sudoku.

“The good Captain is with you?” Thor asks.

“Yeah,” Tony says, wiping his mouth and putting the juice back. This gains him a louder noise of disapproval. “We’re science-ing.”

“You two have been science-ing rather a lot,” Thor observes mildly. “I pray you do not forget that there are others who enjoy your company.”

“Are you feeling neglected?” Tony asks incredulously.

“He just means that it’s been a while since we’ve seen either of your for more than five minutes,” Natasha says. “And he’s right. Steve hasn’t been at our sparring sessions.”

“Huh,” Tony frowns. Steve and Natasha’s work-outs have been a tradition for quite a while now, and Tony’s caught more than a few – they do make quite the sight, after all. “I’ll mention it?”

“Thanks.”

“You and he must join us for dinner,” Thor exclaims. “I am cooking a renowned Asgardian delicacy.”

Tony’s eyebrows climb. “You’re cooking?”

“Yes,” Thor says, self-satisfied, “bilgesnipehove.”

Tony makes a strangled noise and looks at Natasha. He has no idea what that is, but anything with four syllables is bound to do some serious damage to his kitchen. “Please tell me you’re helping him.”

“Clint is,” she says, and he breathes an exaggerated sigh of relief. Thor just laughs, like the good sport he is.

“Anyway, guys, gotta get back to the science-ing,” Tony says, and leaves for the elevator, Natasha’s dry “Sure” following him.

Back down in the workshop, he finds Steve scribbling, almost hidden between Tony’s super-pedagogic visualization of different theories. It still makes Tony pause, seeing him like this – so comfortable in Tony’s space, making himself so at home that the workshop doesn’t just shout Tony anymore, it’s got crooks and nannies that are all Steve.

The sight of it all makes Tony ache.

“Hey,” Tony says, and Steve blinks and smiles wide.

“Hey.”

“Natasha told me you’ve been skimping out on your ‘sparring sessions’,” Tony says, making air quotes. It’s a running gag. “Does that mean I’m not to expect any dirty stories from you this week? Not that you ever share, this bastard.”

“Oh, damn, I completely forgot,” Steve says. “And last week I had a headache, I hope JARVIS told her so she didn’t wait for me.”

“.. you had a headache?” Tony asks. “Did Clint tell you what that means in this context?”

Steve shakes his head and looks questioning. “When working out?”

Tony takes pity on him. “Never mind,” he says. “Oh, and a general warning – Thor’s making dinner tonight.”

Because Steve is not a reasonably suspicious person, and puts too much weight on second chances, he doesn’t immediately look like he wants to hop on the ‘let’s stay down here and eat take-out’-train Tony was about to suggest. “What’s he making?”

“Bilgesnipehove?” Tony repeats, mangling the pronunciation. Now Steve winces. “What? Do you know what it is?”

“He mentioned it to me once,” Steve says. “I must’ve been mistaken, though, because he made it sound like it was a ... head?”

They exchange a wide-eyed glance.

“Let’s hope you’re wrong,” Tony says finally. “How’s the math going?”

“I’m done, let me show you,” Steve says, and Tony lets himself be reabsorbed into their world of numbers.

*

(Steve isn’t wrong. Tony hasn’t had food poisoning since college, and he finds he hasn’t exactly missed it.)

*

Sometimes, Bruce joins them, and Tony knows he’s smiling too wide, laughing too hard. He can’t help it – he’s been dreaming of this for too long. Before he started going there, he thought MIT was going to be like this – an intellectual haven full of like-minded people, people who wouldn’t ask him to slow down or look at him as if he were a freak. (Then he’d begun attending, of course, and found out the reality was vastly different. The way he was so thoroughly, indefinitely ignored by the hard-working students of MIT was so worse than the bullies of his high school, who’d spit in his face and call him a fucking weirdo, how does it feel coasting on daddy’s money?) But he still remembers the dream of MIT being a place where Tony could just be himself, terrifyingly clever without having to consider other people, and that’s what this is. Bruce and Steve are able to follow his train processes, even add to them, and that’s amazing, that’s – he wants to kiss them both and never let them go, lock them in his workshop so they can sit in this couch forever and Tony can feel this forever, the three of them dictating equations at JARVIS and working out hypothetical scenarios for the most ridiculous things.

“Say you have a black hole,” Tony begins, and Bruce groans.

“No,” he says, “I veto everything with black holes. I’m a chemist, Tony, not Watson.”

“I’ll have you know JARVIS is much smarter than any creation of IBM on his worst day,” Tony sniffs. “And with a much better moral compass, didn’t Kubrick teach you anything? Come on, man, live a little!”

“Say you have a black hole?” Steve repeats, and Tony turns to him with a laugh, perpetually surprised by his presence. He slings an arm over Steve’s shoulder, gestures with the other one to encompass the entire world, and says,

“Say you have a black hole.”

*

Tony’s up for a three AM snack when he finds Steve in the kitchen, rubbing at his temples with a tense expression. Steve barely acknowledges him as he enters, and Tony bumps him with his hip as he walks by to get to the fridge. “You okay?” he asks, rooting around for some cheese in between Natasha’s yoghurt and Clint’s half-eaten hamburgers.

“Yeah,” Steve answers after a while. Tony turns around and gives him an unbelieving look. “I, really, I’m fine – just headaches, I can’t get to sleep.”

“Sucks, I know that one,” Tony says. He slaps together a sandwich before getting ready to leave, turns to Steve with a glint in his eye. “Hey, you want to invent something?”

“I— sure,” Steve says, a mildly bewildered smile relieving his features of the tight frown.

*

“Jesus fucking Christ,” Tony curses, long and loud, as Steve finishes writing his equation on the tablet. “You have never been as sexy as you are right now,” he says fervently, and Steve grins.

“Told you I could do it.”

“You could, you could, you absolutely could, I— oh, hey, but what if we add the— or wait, maybe divide the variables by— gimme that, let me try.” He nabs the tablet, and, after a thoughtful silence, adds a few lines. He gives it back with a grin, and Steve reads it with a wondering expression, looks at Tony with wide eyes.

“That’s genius.”

“Isn’t it?” Tony says smugly.

*

Steve doesn’t ask about the arc reactor technology, and it makes Tony ridiculously grateful. The arc reactor is difficult - it’s Howard’s in a way few things are, except Tony bled for it and nearly died for it in a cave in Afghanistan, and he’s earned the right to call it his, his miniaturized arc reactor, his heart. He knows the blueprints for it are easily attainable online, doesn’t fool himself into thinking it didn’t get leaked somewhere between here and Russia, and he knows Steve has probably looked it up, but Tony still appreciates the courtesy of not asking him, of letting him pretend Steve doesn’t know anything about it.

*

They are at the same level, now. Tony doesn’t want to think about that, doesn’t want to think about that might mean – he’s lost in the haze of being challenged, of having to stretch his limits and think. While Bruce could follow him, Bruce couldn’t be forcing him to think like Steve is now – he hasn’t had to think like this since Afghanistan, and even then it was more of an epiphany in between lungfuls of air, a miniaturized arc reactor appearing before his eyes. This is like running when you’ve spent your life walking, something Tony has only experienced once when cooperating with that douche Reed – and that was nothing like this, because this is Steve, and no one will ever compare to Steve.

Tony knows his eyes must be fever bright, feels like he’s drunk or high or building up to the most wonderful orgasm ever as he paces, shouts words and numbers and variables at Steve and JARVIS, mind working lightning quick when Steve shoots down his suggestions one by one, finding ways to circumvent premises and pesky laws of nature, and Steve gets up and says, “Wait, listen, what if you— Tony, what if you changed the cerebral cording to force decompression?

And Tony stops, looks at him with wide eyes, and Steve gives him a tentative smile, growing as JARVIS adds in, “That would appear to solve the problem, sir.” Tony whoops, barely restrains himself from kissing Steve and gives him a hug instead, slapping his back and hurries to write it all down, to make JARVIS draw it up before this rush of brilliance fades, before this endless sea of numerals and blue eyes collapses in on itself.

*

It takes a few months, but Steve eventually asks about the suit.

Tony is, after getting a few moments to react by himself, delighted. Iron Man is part of him, the only part worth anything, and to this day, only one man other than Tony knows how it works. The blueprints are deleted off his server regularly, making the only permanent storing space Tony’s head – just a piece of the armor could do a lot of damage in the wrong hands. To boot, Yinsen only knew the prototype, the roughest of the rough of sketches – Iron Man today is something very different than it was in that cave, and Tony is vibrating with the possibility of showing it off.

As he’s showing Steve the armor, Steve slowly dissecting a stabilizing calf repulsor with an intensity that makes Tony warm, Tony suddenly realizes the implications of Steve being the second person ever to see this, to understand it. Abruptly, the moment feels unbearably intimate, and Tony grows hot underneath his shirt collar. Steve’s hands run over the armor, inspecting how the metal folds on the stomach, the lines of wiring running down the exposed thighs. Steve is peeling away the steel-vibranium shell inch by inch, even though Tony’s explained his several different disassembling techniques – he is unwrapping Iron Man, but more than that, he’s unwrapping Tony.

Tony doesn’t want to analyze how that makes him feel, but there’s a tight grip around his heart that’s both terror and exhilaration.

*

“Tony?” Steve asks, and he’s timid in a way Tony thought he’d forgotten, holding some papers in his hands. Despite Tony’s best reasoning, Steve still uses paper, the artist in him showing. “Are you free?”

“Yeah, what’s up?” Tony asks. He’s sprawled on one end of what has now been dubbed the Couch of Cleverness, tapping out a rhythm at his hip.

“I have something to ask you,” Steve says, and the papers flutter. Tony’s heart starts to pound, just a little. He knows – he hopes he knows – what Steve will ask, has felt it building – has, unconsciously, waited for Steve to acknowledge it before doing anything.

“What?” he presses, when Steve dawdles.

“I was just wondering,” Steve pauses, and Tony wants to rip his own hair out in impatience. “If you used ununseptium for the inner walls and forced the fusion process, wouldn’t that react with the vibranium and cause greater efficiency and less power bleed?”

Tony blinks. And blinks. The warmth that was spreading in his stomach is doused in cold, hard fear. “What?” he grates out.

Steve, looking down at his papers, doesn’t notice. “I thought about it last night,” he says. “Look, I did the math—”

Tony moves like the air is molasses, and it’s about as easy getting it into his lungs. Numbly, he takes the papers from Steve. An exploded arc reactor is carefully, precisely rendered on one page, then several pages of equations follow, ending with an exploded view of Steve’s improved arc reactor. He knows his face is drained, but he can’t get any words out. Steve lays a hand on his shoulder, and Tony forces his face into a light frown. He knows what this means, but he can’t – won’t – focus on anything except this kneejerk sense of betrayal.

“I’m sorry if I overstepped,” Steve says, and his hand is heavy on Tony’s shoulder. “I only—”

“JARVIS,” Tony interrupts. “What’s it look like?”

“Captain Rogers’s calculations appear to be correct, sir,” the AI tells him tactfully, and Tony looks down at the numbers, studying each of them carefully.

He doesn’t understand it.

He doesn’t understand any of it, and Steve is still looking at him with that hopeful expression, and Tony has no idea how to say sorry, buddy, guess I’m too stupid for you now too.

*

Since he can’t in good conscience force Steve out of his workshop, Tony has to get horrifically drunk in his own rooms. He can be altruistic, even if it feels like it might kill him – it solidifies Steve’s betrayal by making him lose his safe space, his haven, even though Tony rationally knows he could just say the word and Steve would make it like he were never there. (That would be equally as bad.)

But Tony’s selfish, and he clings to this reason for feeling like he feels, even though it’s unfair to Steve. It’s better than Steve’s smarter than me and I can’t handle it, makes him feel less like a petty bastard. Hell, Reed is smarter than him, and Tony deals with that okay, even if he personally thinks Reed is a bag of dicks. But this isn’t Reed, this is Steve. Steve’s an Avenger, and Tony is supposed to be the genius of that bunch, okay.

He takes a swig of his drink and stares out into the night. He still has the glass pane layout from his Malibu house, even though the view is quite different - waking up and being able to see New York does wonders for his nightmares. The thought of those now makes him shiver and take another sip.

He feels expendable, is what it is. “Big man in a suit of armor,” Steve once called him, “take that off, what are you?” “Genius billionaire playboy philanthropist,” Tony replied, instinctively, even though playboy’s not true – hasn’t been since before Afghanistan. And now, he’s still a genius, but it doesn’t matter anymore. Steve can do anything he does, and do it better. As for philanthropist – hell, any one on the street can be one, so Tony’s left with his money.

Tony Stark is the Avengers’ money bag, their landlord and bank, but nothing more.

(He always knew this would happen.)

*

Tony gives himself some days to wallow in self-misery. He’s very good at throwing himself a pity party, and this time is no different – he has no hangover because he never sobers up, and both Rhodey and Pepper get a series of voice mails about “remember when I was, indisputably, the smartest guy on the team? Those were good days, right?” and “Rhodey, snookums, honeypeach, pick up, remember college? Reminisce about college with me, Rhodey, please—”

(Just once, Pepper picks up, and Tony’s voice withers in his throat at the sound of hers. He hangs up without a word. It’s probably for the best.)

He writes lists, too. (Well, he dictates them to JARVIS, same difference.) Lists detailing why Tony is still smarter than Steve (those are very short, and boil down to I have more experience and also I am handsomer – Tony isn’t a very focused drunk), why Steve’s smarter than him, why Tony should’ve expected this and he really has no one to blame for not preparing him but himself, and a last one detailing all the ways Tony can now humiliate Reed through Steve.

He’s gone for a long time without binge drinking like this, and the alcohol feels like acid on his tongue, his stomach rolling, but damn it, Steve’s not allowed to take everything from him.

After three days of Tony getting thoroughly bored with his New York view, he hears Bruce’s unique way of knocking.

“Whassit?” he shouts, tries to get up from where he’s slumped against his bed.

“Steve needs you,” Bruce says, momentarily pausing as he takes in the mess of Tony’s bedroom. “Do I even want to ask?”

“Pro’lly not,” Tony admits. “Whass Steve want me for?” He winces. “No, I mean— What’s Steve want me for?”

Bruce gives him a look. “His headaches are worsening, and they aren’t letting up. He’s in some serious pain right now, and I need you to pull yourself together and come see what you can do.”

“Oh, shit,” Tony says. His head clears for the first time in days. “Can I – take a shower first?”

Please,” Bruce says, and supports him when he staggers on his way to the bathroom.

*

After a long shower ruined by worry for Steve, Tony’s all cleaned up, and he feels all the better for it. To contrast, Steve looks like hell. He’s sitting in the kitchen, the room empty but for him.

“Tony!” Steve says as he sees him. Steve’s fists are clenching and unclenching, and there’s a hint of sweat at his brow. “Are you alright?”

“I— me? I think I should be asking you that, Cap.” At the sound of his voice, Steve simultaneously looks relieved and barely suppresses a flinch. Putting two and two together, Tony falls to his knees before him. He fits both hands on the side of Steve’s face, ignoring how that makes him tense up, and cups them over his ears, blocking out the constant hum of the refrigerator and, more distantly, the city that never sleeps. Steve’s sigh of relief is almost unnoticeable, but his murmured, “Thank you,” is not.

Tony’s lips quirk, and he rests their foreheads together, waiting for Steve to relax, for his hands to stop moving. Steve’s eyes slip closed, and Tony takes the opportunity to study his face. Now, he sees clearly all the signs he missed before – the beginnings of dark shadows under his eyes, the proof he hasn’t been eating enough – and feels like a moron, so fucking stupid to have missed it.

“Your breath smells like alcohol,” Steve murmurs, breaking Tony out of his thoughts. His eyes slip open a little to regard Tony.

“Sorry,” he breathes.

Steve moves his head a little back to shake it. “It’s okay,” he replies, just as quietly.

His shoulders stay tense, and Tony can tell he’s not helping as much as he wants to. He hears a door open behind him, didn’t realize Bruce had closed it, and Bruce saying, “Tony.”

Tony reaches down to grip Steve’s hands, fits them over Steve’s ears. Steve rolls his eyes at him, then looks like he immediately regrets the action – Tony raises his eyebrows in a told you so-gesture, and Steve obediently keeps his hands over his own ears as Tony stands up and exits the room.

“He can’t stay here,” he says as soon as the door’s closed, still speaking in hushed tones.

Bruce nods. “It gets worse when he tries to do problem solving, and he needs to be distracted from that. His senses, especially sound, seem hyperaware. I think his brain is overloading.”

Great,” Tony says sarcastically, giving Bruce a look.

“I read about it when I studied Zola’s research.”

“And you didn’t mention it until now?!” Shouting without raising your volume is an art Tony hasn’t really mastered, so he settles for gripping Bruce’s shoulder.

“I didn’t remember until now,” Bruce says, obviously fighting to stay calm. Tony, in a rare act of self-preservation, lets go of his shoulder. “It was Red Skull research, it was irrelevant to my studies – Erskine’s research showed nothing of the kind, but they never put Steve’s brain to this much complex thinking.”

“Is it lethal?” Tony asks, hating himself for having to.

“I don’t know,” Bruce says. “Possibly.”

Tony takes a deep breath and rubs the bridge of his nose. It isn’t really Bruce he wants to shout at, it’s the part of him that viciously, gleefully whispers, see, this is what happens when you try to out-smart Tony Stark, only held in place by the guilt coursing through his entire body. “Okay. There are some sound-isolated rooms further down in the Tower, we’ll clear one and put him there. Distractions, you said?”

Bruce nods.

“What, like trash TV?”

He shakes his head. “Books – fiction – Natasha’s sudoku, drawing, I can’t come up with anything specific right now. What do you do when your head gets too much?”

I have a drink and hang out with Steve, Tony thinks, but that probably wouldn’t do Steve any good at all. I have a drink and I find a warm body, except Tony doesn’t, anymore, and that definitely wouldn’t help. “I watch nature documentaries,” he says finally, because Bruce looks like he’s still waiting for an answer. “I take the suit for a spin. Shit, Bruce, I don’t know. What are we going to do?” He blames the alcohol still in his body for the way his voice almost cracks, for the fleeting glance he throws the kitchen door.

“We’re going to fix him,” Bruce says, and Bruce is amazing, Tony has definitely neglected his friendship with Bruce in this whole wow, Steve is super smart-thing. He remembers the shy, uncertain doctor he met on the Helicarrier, compares it to the firm and unashamed Bruce standing before him, and really hopes he didn’t miss out on that process. “Now, I unfortunately can’t give him anything for the pain – the amount he’d need to feel it is too dangerous to his systems.”

Tony nods, and looks toward the door again. He imagines the Steve sitting on the other side, looking lost and in pain, and the stone in Tony’s stomach grows heavier. It’s all my fault. “I’ll go set the room up,” he says, and leaves before he goes back in to Steve.

*

“Bruce, Bruce, tell me what I can do to help,” Tony says, roaming around Bruce’s laboratory. They’ve set up the room, and Natasha’s outside it right now, standing guard. The room is, unfortunately, in one of the working levels, and a lost and confused worker might find their way there accidentally. Thor’s in Asgard, and Tony’s of half a mind to ask him to bring back some magical concoction, though he doubts this is a problem the Asguardians face often.

“You can leave,” Bruce says.

Tony gasps, mock-affronted. It’s probably ludicrously inappropriate, but Bruce knows how he deals. It’s fine.

Bruce takes off his glasses and cleans them on his shirt sleeve. “I’m serious, Tony. Go sober up, you still look like you’ve spent the last three days drinking yourself into a stupor. I’m amazed you’ve been as put-together as you have.”

Tony’s eyes shutter.

“I know you care about him and I’m not attacking you,” Bruce says, not unkindly. “But I need you at your best, okay? Steve needs you at your best. I’ll do the grunt work while you go eat, please.”

Tony grumbles but complies, and that’s how he ends up sitting on the kitchen floor with Clint, each of them eating solidary our team mate is going through a terrible time and we can’t do anything about it and that sucks-sandwiches. Tony and Clint make very elaborate and eloquent sandwiches – it keeps them from ever, ever having to discuss their feelings.

*

The next day, Tony visits Steve.

The only sounds in the room are Steve’s claps between each push-up. Tony’s sitting on the bed, eyes resting on Steve’s form.

“How you holding up?” he asks, finally.

“Fine,” Steve says. He doesn’t stop, doesn’t even falter.

“What number are you at now?”

“Four hundred and twenty seven,” Steve says.

It’s the next day, and Steve looks better. Well, relatively – not enough that Tony can just brush all of this off, pretend it was a fluke. Enough so that he knows the room helps, though, which is good. “Huh.”

Steve continues pushing off the ground. Clap. Clap. Clap.

“Where does it start?”

Steve lets out a small sigh and stops, low to the ground. "Frontal lobe,” he says, “usually.”

“That makes sense,” Tony says. “And then?”

“Primary auditory cortex, general occipital lobe, it varies.”

“Hm,” Tony says. “Do you think you could solve this?”

“No, I—“ Steve sits up, rubbing a hand across his forehead. “I really don't think so.” His voice is lower, harsher, and his eyes are closed. “Please stop asking.”

“I'm just saying,” Tony presses, “if it comes in waves, then—“

Please,” Steve says, and he almost sounds like he's crying, both palms pressing against his temples. His breathing is short and quick.

Tony shuts up immediately. He sits there until Steve's breathing evens a little, then: “I'm sorry.”

“Don't,” Steve says tiredly. “Just – go, I think, Tony.”

He doesn't look up as Tony exits.