Warnings: Abusive relationship, issues with consent (consent obtained via false identity, consent unable to be withdrawn), passing reference to suicidal thoughts.

Notes: This was written in response to a prompt on Avengerkink over on LJ. Also, FF keeps eating my scene breaks and their own inserts don't look very nice, if you want to read this with the intended formatting it's up on AO3 under the same username.

It's two days after the fight against Loki. They're sparing. Steve flips Tony, pins him down and suddenly they're kissing. To Tony, it comes as a total surprise. A very, very good surprise, but an 'oh my god, never imagined this would actually happen' surprise nonetheless. Things happen so fast it's dizzying. One minute they're fighting and the next Tony's pants are tangled round his ankles and Steve's moaning in his ear. It's over almost before he registers it's begun.

His heart is beating so fast he can hear it and feel it thrumming through his whole body. Between heavy breaths he struggles to form coherent words. 'God,' he says eventually, 'that was so good.' It's a rather inadequate response, but his mind's still struggling to catch up with his body. He's actually pretty proud that he manages more than a groan.

Steve's answering smirk is infuriatingly smug but it's Steve, so Tony lets it pass (besides, Tony's never been fond of throwing stones and he's just about preening with self-satisfaction right now). 'We should do this again sometime,' Tony says, mind now sufficiently caught up enough to attempt intelligible speech.

'Maybe.' And for a moment Tony's chest flutters with disappointment, sure that Steve's about to tell him this was a mistake. 'But away from the cameras next time?'

Tony's eyes shoot up to the security camera in the corner of the room - it's trained right on them. Tony had completely forgotten it existed. The things Steve does to his mind would be disturbing if he could bring himself to care. He winks at Steve. 'Think I'll keep today's tape for my private collection.'

Steve flushes. And isn't it just so damn adorable that after what they've just done quite shamelessly, Tony's one-liners could still make Cap blush.

Tony doesn't stop smiling for the rest of the day.

He doesn't stop smiling the next day either. Waking up next to a sleep tousled, half-naked, sexed-out Captain America is only a thousand times more satisfying than he'd ever imagined it (and he'd imagined a lot).

It doesn't take long for the rest of the team to notice something's up. They're not trying to hide it after all. Besides, Tony doesn't think he could hide just how stupidly happy he is, even if he was trying. His jaw is starting to ache from all the grinning (and probably the other things too).

'So.' To Tony's surprise, Hank is the first one to comment. 'You seem different lately, Tony. Is something going on?' They're in the labs, working together on an upgrade for the mansion's security and the question takes Tony by surprise. Normally when he and Hank are working on something, conversation between them is strictly professional. They both have a tendency towards single minded focus that doesn't lend well to idle chatter when working.

Tony sets down his welding torch and turns to look at Hank. 'What do you mean?' He knows full well what Hank means, but it amuses him to play dumb.

Hank raises an eyebrow. 'You're awfully happy lately.'

Tony smiles smugly. 'I am, aren't I?'

Hank pauses then clears his throat. 'It's Steve, isn't it?'

Tony's grin widens. He bites the inside of his cheek to try and suppress it. 'Might be.'

Hank shakes his head and sighs. 'Just don't screw it up.'

Tony would feel insulted but he's knows that's not going to happen this time. He won't screw up, because he won't let himself. He's supposed to be a genius, after all, and only an idiot would screw up a relationship with Captain America. 'I won't,' he tells Hank, and with a solemn shared look, they both go back to work.

He spends the next couple of weeks of work, training and rescuing the elderly from burning buildings, in a haze of sexual gratification and tries to tell himself that's all it is. Because Tony Stark does not fall in love (except maybe, when he totally does).

His state of buzzing enthusiasm seems to be putting the other Avengers on edge. They won't say it, but Tony's pretty sure they're all thinking the relationship can't last. Tony knows he has a playboy reputation and he's always been fine with it because it's just that, a reputation. Maybe there's some truth to it when he's single and just looking for a good time, but he'd never cheat on a partner. He'd never cheat on Steve. For one thing, no one could compete with the amazing sex anyway. For another, Tony will admit only to himself, he's pretty sure this is what it feels like to be fucking smitten.

So maybe he does smile a little more often and maybe he does talk about Steve a little too much and maybe he does sit a little too close to Steve on movie nights but he has as much right as anyone to be happy. Even if he does secretly feel like he doesn't deserve it.

It's two weeks into their relationship and a little over halfway through the third team movie night since they got together, when Steve gives him a tap on the shoulder and cocks his head towards the door, raising his eyebrows with a suggestive leer. Tony smirks and nods.

'Well,' Steve says as he rises to his feet, 'I'm exhausted. Off to bed. I'll see you all tomorrow.'

'Yeah, me too.' Tony gives an exaggerated stretch and yawn and get up to follow Steve. 'I'm beat.' Hank raises an eyebrow and tilts his head in a way that says they're fooling no one. And in the corner of his eye he sees Jan give an exaggerated shudder.

Clint rolls his eyes. 'Oh just go get laid and let us watch the movie already.'

'Well,' Tony laughs, 'I know I'm not the best at following orders, but I think that's one I can handle.' He gives a mock salute and follows Steve to the bedroom.

Tony closes the door behind him with a soft click and smiles at Steve. 'So -' he says.

Steve holds up a hand to silence him. 'Wait a second.' He grins sheepishly and rubs a nervous hand on the leg of his pants. It's enough to draw Tony's eyes to his crotch where they linger as Steve crosses the room. 'I've been thinking…'

Tony's eyes drift back to Steve's hands as he opens the dresser and pulls out a length of rope. Tony's jaw tenses, because he can see where this is going and he knows it's too soon. It's not that he doesn't trust Steve - because Steve is Captain Fucking America, if anyone in the world can be trusted to do this safely it's Cap - it's just that he doesn't trust himself. He doesn't know that he won't panic; doesn't know that he won't forget who he's with and where he is and if that happens, it would ruin everything.

'I thought we could try something different,' Steve says as he dangles the rope in Tony's field of vision. There's an almost maniacal grin on Steve's face that removes the last traces of hope Tony had held, that maybe Steve wanted to be the one getting tied, not doing the tying.

Tony hesitates, choosing his words carefully. He doesn't like saying no and feels a little uncomfortable admitting that he doesn't want to do it, but he's smart enough to know he can't fake his way through this one. He's sure Steve will be good about it. 'I'm… not sure I'm entirely comfortable with that.'

Steve's grin falters. 'Oh come on, Tony, I'd do it for you!' Guilt bubbles up in Tony's belly, because he knows it's true. Positions reversed, Tony's sure that Steve would at least try. The thought nearly makes Tony change his mind, but he thinks about the feeling of rope around his wrists and he thinks about the consequences of an inevitable panic attack (Tony will not have Steve thinking he's weak, even if it is true).

'It's just, I have a little thing about being restrained. Bad memories, is all. I want to. Really, I do. I'm just not sure it's a good idea right away.'

'Don't you trust me?' Steve looks and sounds so hurt that the guilt spikes painfully in Tony's chest and stays there making him feel queasy.

'It's not that.'

Steve drops the rope to the ground with a sigh. 'Yeah. Sure. Fine. Whatever.'

Tony winces. 'Sorry, Steve.'

Steve huffs. 'Sure.'

'Can't we just…' Tony steps closer and puts his hands on Steve's hips. He tries to hide the simmering guilt with a half-hearted leer and a suggestive hip wiggle, but he doesn't feel it. The sense of regret has settled in the pit of his stomach and any promiscuity he'd felt early has been replaced with a feint sense of nausea. But hey, he's Tony Stark and sex is sex, whether he feels like it or not. Plus he really needs to make this up to Steve.

Steve pushes Tony's hands away and turns his back to him. 'I'm tired, Tony. I'm just not in the mood.'

'You were in the mood a minute ago!' Hello foot, meet mouth. So much for Tony Stark the genius.

'I was in the mood for something different, Tony, you're the one who changed that.' Steve strips down to his underwear and slides in under the bed sheets. 'I'm tired of the same stuff.'

Tony hops on one foot as he attempts to remove his shoes while still looking at Steve. 'Hey, I can do different! I can do all kinds of different,' he says lightly as he strips off his shirt and hangs it on the back of a chair. 'I just need a little more time before we go down that particular rout, okay?' Steve just grunts and turns his back as Tony slides in next to him and goes for a bear hug. Tony elbows him in the back. 'Oh come on, honeybear, don't sulk.'

Steve sighs. 'Just sleep, Tony.'

This is the best thing he's had in so long and already he's managed to screw it up. Before he can fuck things up any worse, he decides to keep his mouth shut. He lies awake for five hours, watching Steve sleep and thinking of ways to make it up to him.

Tony wakes up alone the next morning. His heart drops a little when Jarvis tells him Steve's not in the mansion, but he reminds himself that he probably just went for a morning jog. That's perfectly normal Steve behaviour.

Instead of dwelling, he grabs some clean towels and goes to take a shower. He forces himself to mentally go over the schematics for his latest suit upgrade instead of replaying the night before for the seventh time. But the water pelting his face and reminding him of why he's not a fan of showering makes it difficult to keep his mind from more dangerous pursuits.

A few minutes later, he slips into a robe and slippers, drapes a towel over his shoulders and shuffles towards the kitchen in search of coffee. He tells himself for the sixteenth time that Steve's just gone for a run.

Clint's in the kitchen pulling faces at a bowl of burnt porridge (you can burn porridge?) but he perks up the moment he sees Tony. 'You two lover boys have a falling out?' He sounds disconcertingly cheerful about the prospect, but more importantly, where the fuck did that question come from?

'What makes you think that?' Tony asks, rubbing his hair dry with the towel as a ruse to cover his face while he desperately fights for composure. He aims for casual, but probably misses by a long shot if Clint notices the croak in his voice as he says it.

'You two have been coming in for breakfast together every day for the past two weeks. Today Steve comes in looking grumpy, refuses to talk to me then goes off for a run.' There. See. Steve really has gone for a run.

Tony sighs and fetches himself a cup of coffee. 'It's nothing, Clint.'

Clint's mischievous grin falters for a moment. 'Seriously though, are you guys okay?'

'Yeah, it's nothing. Just… nothing.' Because it is. Nothing. Steve's just a little disappointed and sexually frustrated and everything will be fine once he's had a chance to think about it. Which is probably what the run is about anyway.

Clint watches him dubiously for a moment, but thankfully says no more. A slightly awkward silence descends as Tony finishes his second and third coffee and Clint pushes his porridge around a little. It's made all the more awkward the moment Steve walks in.

Steve stands by the door for a moment and looks at them. Then he nods. 'Tony,' he says neutrally as he walks in and gets himself a glass of milk.

Tony nods back. 'Steve.' Steve takes a seat across from Tony and stares intently at him. Tony fidgets, drinks his forth cup of coffee and avoids looking directly at Steve.

'Okaaaay,' says Clint, edging out of the room after the awkward silence goes unchallenged for a solid two minutes. 'I'll just leave you two to it.'

Alone at last, Tony finally looks at Steve. 'What's with this passive aggressive bullshit, Steve?'

Steve splutters and chokes on a mouthful of milk. 'What?'

'You're looking at me like I've done something terrible.' Tony stands and turns his back to Steve, under the pretence of refilling his coffee. 'If this is about last night, I didn't even say no - I said not yet. You want me to say okay to something I'm not comfortable with? Is that it? You're so desperate to get your rocks off that you don't even care about what I want?'

'No, it's not like that.' Steve's hand is on Tony's shoulder. Tony tenses. But only because he hadn't heard Steve get up. 'Look, I'm sorry, Tony.' He turns Tony around and puts both hands on his shoulders this time. 'I was just… frustrated. You know how it is?' He gives Tony a peck on the cheek and pulls him into an embrace.

Tony laughs and nuzzles against Steve's shoulder. He should probably still be pissed, but it's too difficult for him to resist snuggling with Steve. Goddammit, Steve knows all his weaknesses. 'Yeah,' he mumbles into Steve's shoulder, 'I know what you mean.'

'So,' Steve slides a hand down the back of Tony's pants, 'make it up to me?'

Tony groans and rolls his hips. 'That I can do, soldier.'

Steve nips at Tony's ear, grabs his wrist and all but drags him to the bedroom.

The next thing Tony knows one of Steve's hands is tangled in his hair, tugging so hard it brings tears to his eyes and makes him feel like his scalp is on fire. His other hand is wrapped around Tony's bicep so tightly it's almost unbearable (and Steve's a fucking super soldier, if he squeezes much harder he's going to break bone). Tony just grits his teeth and clutches the bed sheets because he can't ask Steve to stop. He won't. After last time, that would be too selfish, even for him. Besides, he's Iron man, and if he can't handle a little rough treatment now and then, he should probably give up being a superhero. Steve being Steve, he probably doesn't even realise he's hurting him and will guilt-trip and puppy-dog eye himself through the whole next month if Tony tells him. Hell if Tony's going to put up with that.

Steve's going faster, thrusting harder, and, shit, it really hurts - he's going to be very sore after this. Tony's arousal is quickly fading, but he doesn't say anything. He's felt worse pain, in less pleasant situations. He can handle this, because it's obvious now that this is what Steve likes, and he won't deny him that. So he holds back the pained grunt and just lies there and takes it.

When he's finished, Steve rolls over with a satisfied grumble and goes to sleep. He doesn't even notice Tony's lack of arousal. Tony tells himself it's probably for the best; there are no awkward conversations this way.

After a few minutes of watching Steve sleep, Tony gets cleaned up then heads to the labs. He spends the rest of the day working and trying to ignore the pain.

A few days later Tony finds Steve in the living room, watching TV. He takes a seat next to him and shuffles close enough that their shoulders are touching. 'So what are we watching tonight?'

'There's a documentary about renaissance art starting in a couple of minutes.'

'God, no. We're not watching that.' Tony snatches the remote from Steve's hand and starts channel surfing.

'Hey!' Steve leans over to take the remote back but Tony shuffles away and holds it out of reach. Maybe a bit of play fighting can lead to something a little more fun than art documentaries, if he plays his cards right. 'Give me that.' Steve makes a grab for the remote again but Tony yelps and slides onto his back, pushing Steve away with his foot and holding the remote out over his head.

'Tony, stop!' Steve grabs his wrist, pulls him back into a sitting position, yanks the remote from his hand and scowls at him.

'Huh?' Tony's can't think of anything more articulate to say; he'd thought they were just messing around but Steve actually sounds pissed now.

'We're watching the damn documentary.' Steve flicks the channel back and with one last glare turns back to the TV.

'Oh.' So, that had been a misjudgement. Only Tony Stark could screw up something so simple. 'Um.' Tony scratches the back of his head. 'Sorry?' Steve grunts but doesn't take his eyes off the screen. For a genius, Tony Stark couldn't half be a fucking idiot.

Tony figures the whole rough sex thing hasn't been going too badly. Maybe he feels obligated after pissing Steve off, or maybe it's just his general disregard for self-preservation, but that night he suggests they try Steve's something new.

Steve just looks confused. Tony sighs. That's the last time he tries to avoid a touchy subject with euphemisms. He holds his hands together out in front of him. 'Make with the rope, Captain Rogers.'

'Really?' It's much more like a high-pitched squeal than anyone who isn't a thirteen year-old girl should be capable of.

Tony laughs half-heartedly. 'Sure.' Steve bounces around like an overexcited puppy as he gathers the ropes from the dresser. Tony watches. He taps a finger restlessly on the bed post, nodding his head to an imaginary beat and counting each tap. One, two, three. One, two, three. If he can just keep counting and focus on keeping the rhythm, he won't have to think too much about what he's about to do. What makes Steve happy makes him happy, so he can do this. Even if it's not exactly his own idea of a good time.

Steve dumps the pile of rope at the foot of the bed, pulls Tony close then kisses him enthusiastically. Without a word, Steve pushes Tony onto his back, then kneels down and pulls off Tony's shoes and socks, but leaves him otherwise clothed.

Tony closes his eyes and takes slow, steady breaths as Steve ties the rope around his ankles. It's unpleasantly tight. It slows his circulation and his pants pinch and chafe against his skin every time he moves his legs - which he can't seem to stop unsuccessfully trying to do. It's horrible. But Steve runs a gentle hand up his stomach and through his hair and he kisses Tony's hands as he takes hold of them. That makes it easy.

Steve draws the rope around Tony's wrist and ties a complex looking knot that he probably learned in the goddamn boy scouts. 'God, Tony, you look so hot like this,' he says. Tony tries to smile but Steve pulls the rope just a little tighter and he hisses as his circulation is cut off.

Without warning Steve flips Tony onto his stomach. That's how they always do it. Tony thinks it must be some strange self-conscious thing, because Steve obviously doesn't like Tony looking at him while they have sex. Steve slides a hand under the waistband of Tony's pants and gently tugs. 'Wait,' Tony says. Steve's roaming hand stills, but he doesn't remove it. 'Don't we need… like a safe word or something?'

'I don't think we'll need that, Tony.'

'Yeah, but it can't hurt to have one, just in case.'

Steve removes his hand. 'You trust me, right?'

'Of course. I mean, we're doing this, aren't we?' Tony tries to squirm his way onto his back so he can see what Steve's doing. The ropes bite into his skin with every movement and Steve's still straddling his waist, so it's difficult, but he manages to twist his neck around enough that he can see Steve in the corner of his eye.

'Good.' Steve's says. 'Because a safe word isn't going to work out.' Steve pulls a ball of familiar heavy grey cotton from his pocket, and those are Tony's freaking socks! But before Tony has a chance to protest, Steve shoves them in his mouth and ties them in place with a spare length of rope. Steve strokes a hand through Tony's hair, but it's not nearly so reassuring when his mouth tastes of feet and he can't even tell Steve he's not happy about it.

Tony grunts in protest and tries to turn away to let Steve know he's not happy with this anymore. But Steve must mistake it for something else because he grinds against Tony wriggling hips and pushes Tony's head into the pillows.

Tony tries to relax. He tries to just let go and let Steve do what he needs to, because there's nothing he can do to stop him now anyway (and that's okay, that's okay; he suggested this and Steve would never hurt him).

But the rope's too tight and he can't feel his fingers or toes anymore. This isn't right. He can't do this anymore. He wants to scream stop, stop, stop, but he can't. The gag's making it difficult to breath and Steve shoves his head further into the pillows and all he can feel is cloth against his nostrils and no air's getting in. He can't breathe. He can't breathe. He tries to kick and struggle and anything to make Steve stop. But he can't move and he can't breathe and he can't make it stop. He feels dizzy and sick and he's going to puke and that's not good, not good at all. He can't die here choking on his own vomit while Steve's fucking him and totally oblivious.

Pain grips him in the chest so tight that it feels like he's having a heart attack (and he actually knows what that feels like - he's not just being dramatic). And he can't fucking breathe! There's a tingling hot-sweat running all down his body but he can't stop shivering. And Steve's too busy to notice. His vision's fuzzing around the edges and he prays to a god he doesn't believe in that he's about to pass out.

Steve pulls his hair and it lifts his head away from the pillow long enough that he takes an involuntary deep breath of air. The haze of black lifts slightly. But he wishes it hadn't; he just wants to pass out. Just wants to make it stop.

Steve grunts and trembles and all Tony can think is thank god, thank god, thank god. Steve rolls onto his back and sighs. After a minute, Steve pulls Tony closer and tugs off the gag. Tony coughs and wheezes as Steve unties the rest of the restraints then lies back down.

There's silence between them as Tony tries desperately to catch his breath. 'Can we…' he chokes on the words but manages to turn the threatening sob into a weak cough. 'Can we not do this next time?'

Steve runs a gentle hand through Tony's sweaty hair. 'You were great, Tony.' But he doesn't say anything else.

After that, everything goes back to normal. Except that Tony remains tender from Steve's persistent rough side in the bedroom. But Tony's fine with it, it's nothing he can't handle and he can sufficiently distract Steve enough that he doesn't even notice when Tony enjoys it a little less than he should. Tony's pretty sure it's just some 40's sexual frustration thing anyway. He'll probably stop once he realises it's not necessary. And if he doesn't, well, Tony could get used to it. It's Steve, after all.

They sleep together, have meals with the rest of the team, work out every day and arrest a couple of super villains. Tony takes Steve out for dinner. Steve takes Tony to an art gallery. Nothing out of the ordinary. Steve's the perfect gentleman, Tony's on his best behaviour, and everything's great between them. For a week anyway.

It's early, Tony had a long night in the lab, but he gets up anyway, because Steve suggest they shower together and Tony's never one to look a gift horse in the mouth. After, they have a quick breakfast then Steve suggests a workout. Normally Tony would refuse so early in the morning, but Steve gives him the puppy dog eyes and Tony's like putty in his hands.

They go a few rounds. But Tony's tired and his mind keeps drifting to important schematics he needs to complete.

'What the hell is wrong with you, Tony?' Steve grabs him by elbow and wrist and twists. Tony topples to the floor for the fifth time in as many minutes. He slams his shoulder against the ground and hisses at the spike of pain. 'I've told you this three times already.'

Tony winces as he struggles to his feet and carefully rolls his shoulder. He feels the stiffness that tells him he's getting another bruise for the collection. He crosses his arms and rolls his eyes. 'I'll get it eventually. We can't all be super soldiers.'

Steve huffs. 'You're just slow, Tony. Clint can hold his own just fine, hell, even Hank is better at sparing than you. Face it, the only thing that keeps you from being dead weight is the suit and trying to change that is proving to be a wasted effort.'

Tony freezes for a moment. 'Fine. Whatever.' Tony grabs his towel and bottle of water and storms out of the gym. Times like these he wishes he hadn't given the mansion automatic doors.

He knows he shouldn't be pissed but Steve hit a nerve. He's always known he's a liability to the team; no matter how much he trains and practices he just can't keep up without the suit. He's been telling himself, that's okay, Steve's teaching him, but the truth is he just can't compete. Maybe if he wasn't such a god awful student; maybe if he was stronger, faster, smarter, better. But he's not. He never has been.

God, what's been up with him lately, it's like he's physiologically incapable of not screwing things up. And to make things worse he's being temperamental about it and starting to take things out on Steve. What an asshole.

He figures he should apologise. Instead, he goes to his workshop and spends the next thirty six hours re-designing Cap's shield (he'll need a replacement now the old one's broken). Steve doesn't come to see him once.

He's proud of the finished product. The design is different to Steve's old shield, but it's also lighter and more heavily reinforced. Plus he'd managed to resist the urge to add a variety of useful gadgets that Steve would hate.

It's mid-evening, so the team should be having dinner together. He's too impatient to wait to speak to Steve in private, so he makes his way up to the kitchen. Everyone's there even the Hulk - he guesses it's a team bonding type thing, and even though he would've refused, he can't help but feel a little hurt that no one invited him.

Tony greets the team with nothing more than a nod then hones in on Steve. He taps his shoulder to draw his attention. 'Hey, Steve.' The rest of the team are carefully not paying attention (except T'Challa and Hulk, who really aren't).

Steve nods. 'Tony.' There's a pause. 'What's that?'

'Oh, this?' He holds the new shield up casually, like it's not the sole reason he's there. 'I just made it. It's an upgrade.' He hands the shield to Steve.

Steve gets up from the table, weighs the shield out in his hands then gives Tony a funny look. 'Why would I want this?'

'Well, I thought you could use -'

'God, are you a complete idiot?' From the corner of his eye, Tony notices that Jan isn't pretending not to watch anymore.

'Um, no?'

'The weight and shape affects the aerodynamics, Tony. How do you expect me to throw this accurately?' Hank and Clint are blatantly staring now too, and even T'Challa's watching warily, Hulk and Thor just look bemused. Tony tries to ignore them, but it's making his skin crawl. He should have done this in private.

'No, no. I made sure. The aerodynamics are improved. You should be able to throw it further with less wind resistance. Once you get used to the new design and weight -'

'No, Tony. Don't you get it? I don't want this.' Steve shoves the new shield into Tony's open arms then storms off.

Tony turns to the rest of the team. He chews on his bottom lip and tries to avoid the uncomfortable stares without seeming too pathetic. 'Well, that could have gone better.' He turns and leaves before anyone has a chance to reply.

He takes the shield down to the lab, because as much as he wants to just destroy it, there may be a day when Cap won't have a choice - when he'll need it. And if that means hiding it away in a draw somewhere and pretending it doesn't exist, then fine. Better to be well prepared than let the nauseating feeling of embarrassment supersede his logic.

He stays in the lab all night again because, if he's honest, he doesn't want to face Steve. He's doesn't think it'll lead to an argument, but in hindsight he's pretty embarrassed that he had the audacity to redesign Cap's shield without even consulting him about it. He fixes Steve's shield this time, using the broken pieces to re-forge it exactly as it was before.

He goes up to the mansion around noon, leaves the new-old shield in the gym for Steve to find in his own time, then heads for the kitchen seeking coffee. Jan's there, reading a magazine and sipping a cup of coffee. Clint's there too, stroking his bow lovingly, or possibly polishing it, but Tony struggles to see the distinction. Tony grumbles a greeting and goes over to brew a fresh pot of coffee so he can take back to the lab with him. He's impatiently tapping his foot, waiting, when there's a hesitant pat on his shoulder.

'Tony, can I have a word with you?' Jan asks him. 'In private,' she adds quietly, casting a glance at Clint.

She looks a little nervous, so Tony shoots her his best reassuring grin then follows her into the living room and takes a seat next to her on the couch. 'What's up?'

Jan fidgets and for a long minute she won't look at him. She takes a long, slow breath and releases it in a sigh before fixing Tony with a deadly serious look. 'Tony,' she starts with confidence, then falters, 'I know you're probably going to tell me it's not my business and maybe it isn't, but I'm worried.' Well that doesn't bode well. 'This thing you have with Steve… he doesn't seem to treat you very well, Tony.'

Tony raises an eyebrow. 'What are you talking about?' Tony's not just playing dumb, he is genuinely baffled. For the most part, outside of the bedroom, Steve's always friendly, charming and everything Tony could ever wish for. Yeah, he's been a little distant since Tony's screw up in their sparing session, but they're getting past that now, and it's nothing Jan should be noticing anyway.

'He pushes you around, Tony.'

'Don't be ridiculous, Janet.' He clenches his fists and grits his teeth. He can feel something unsettling like rage beginning to simmer in his stomach. Jan has no right to go making such ridiculous accusations. 'Steve doesn't make me do anything.'

'Maybe not, but he says and does things you wouldn't take from anyone else and you shouldn't take it from him.' And so what if that's true. They're partners, that's normal. Of course he gives Steve's a little leeway, Steve gives him the same, and Jan shouldn't be making him sound like some beaten-down housewife because of it.

He slams his hand down on the couch arm and rises to his feet. 'I don't like what you're implying. Cap's a good man!'

'I know that. That's not what I'm saying at all. I'm just not sure your relationship is healthy; I've seen the bruises, Tony. It's not normal and you can't let him do that to you.'

Tony deflates. So that's what this is about. 'Look, Jan, I know what you think, but it's not like that. He likes that shit, okay?'

'And you? Do you like it?'

'God! I don't have to explain my sex life to you.'

'I'm just worried, Tony.'

'I know. I know. I understand why you're worried, but it's not like that. Really, it's not.'

Jan nods but she doesn't look particularly relieved. 'Okay, Tony. I trust you.' Tony pats her reassuringly on the shoulder, and heads back to the lab.

Stupid Jan. Putting ideas in his head. Tony knows she misunderstood, but it doesn't stop him thinking of her words the next time Steve grabs his wrist when he wants something (why doesn't he just ask?) or the next time he initiates rough sex (why doesn't he ask first?). He thinks it's a bit like seeing a shadowy figure over his shoulder; he knows he's just imagining things, knows it's not real, but he can't help looking once the idea's in the back of his mind.

So maybe Jan's words affect him more than they should. It's completely ridiculous, but he can't seem to get them out of his head. It's just a coincidence, he tells himself, that the next time they have sex, Steve's a little too overenthusiastic. 'Okay,' Tony says between grunts of pain. 'Stop. I want to stop now. Can we stop?' With one last violent thrust, Steve stills.

'What?'

Still, Tony hesitates. He thinks if he really tries he can do this. But there's that little niggling Jan voice shouting at him in the back of his mind, forcing him to test the waters. Making him prove that Jan is wrong. No one pushes Tony Stark around, not even Captain America. 'I want to stop.' Tony slowly releases one of his clenched fists, braces his hand on the headboard and tries to push Steve away with his feet. 'You're hurting me.'

'I need to finish,' Steve says. Tony grits his teeth as Steve's hips twitch minutely.

'Yeah, I know. Just, let's do it another way, okay? I don't really want to do this anymore.' God, Tony can be fucking selfish at times, but if he can just prove to that annoying little Jan voice this once, he won't have to do it again. Besides, he's not lying, he's really not enjoying himself, and he can make it good for Steve without suffering this unnecessary pain.

'God, why are you complaining, Tony? This was your idea.' It's true, Tony had initiated things this time, but he hadn't meant it to go like this. He'd wanted something softer, thought maybe they could do it his way for once. But Tony always gives Steve exactly what he wants. That's what you do for people you care about. Even if Jan doesn't understand that.

Steve sighs but pulls away regardless.

Tony can't hold back a hiss of pain as he rolls over to look at Steve. He spots something in the corner of his eye that makes him freeze. 'Christ, Steve. I'm bleeding.' There are little speckles of reddish-brown drying on the sheets, so Tony sticks a hand down to check and his fingers come away spotted with blood. He has a surge of blind panic for a second before logic takes over and tells him it can't be that bad - there's not much blood and the pain's not much worse than normal; it's just a little superficial tearing. 'I'm not having fun anymore.' But he never really was.

Wordlessly, Steve flips Tony back onto his stomach and Tony has another brief moment of panic when he thinks Steve's about to start up again. But he doesn't. Of course he doesn't. It's Steve. He's just checking the damage. 'You're fine,' Steve says after a moment of gentle prodding. 'It's nothing serious, just a little tearing. It's stopped bleeding already.' With a sigh, Steve throws himself down on the bed next to Tony. He quickly jerks himself off, then pat Tony on the shoulder with a weak smile. 'Sorry.'

Tony shrugs. 'It's fine.' At least now the little Jan voice can shut up. Steve stopped when he asked him to. Steve checked he wasn't hurt. Hell, Steve apologised. Maybe he's even learned to go a little easier from now on.

The next day is hell. Sitting in the lab makes him feel like his ass is on fire. Training's a no-go too, since he can barely walk without limping.

He stays in bed working on a tablet computer until noon. He goes swimming until his fingers are wrinkled and his muscles are aching. He paces, trying to think of things he can do without sitting or kneeling or lying on his back - basically doing anything other than standing in one spot. He sighs and goes to find Steve. Maybe they can play some Ping-Pong or something, that's a low exertion sport, right?

He comes across T'Challa meditating in one of the mansion's many rec-rooms. 'Seen Steve anywhere?'

T'Challa opens one eye to look at him. 'I have not.'

'Oh, well, okay. If you see him… I'm looking for him.' Tony turns to leave.

'Tony?'

Tony stops and looks over his shoulder at T'Challa. He's watching Tony with his full attention now. 'Yeah?'

'I believe your relationship with the Captain is not beneficial. He does not treat you with the respect one ought to show their partner.'

'What?' Tony turns to stare at T'Challa. Where the hell did that come from? He must have been talking to Jan. Where did those two get off sticking their noses into other people's business and making completely unfounded accusations? 'I wasn't asking for goddamn relationship advice. Just tell him I'm looking for him.'

T'Challa shakes his head. 'It was simply an observation.' Then he goes back to meditating, like he never said a word.

Tony doesn't feel like playing Ping-Pong after that, he grabs an apple and some coffee from the kitchen then goes back to his lab. Maybe he'll find something he can work on standing up.

It still takes Tony a while to admit to himself that something might not be quite right. He keeps telling himself it's fine. Jan and T'Challa are wrong. But he can't deny that something's not right, when Steve invites him back to the bedroom one night and his stomach flip-flops in dread. Fuck, he thinks, but he dismisses it and carries on with life.

His ass still hurts every time he moves, every time he sits, every time he breaths. But he never turns Steve down. It's not worth facing a sulking Steve for the next two days just to avoid giving him a blow job (even if it leaves Tony with a throbbing jaw and finger shaped bruises all along his neck). And, yeah, okay, Tony will admit that maybe it's not exactly how he'd imagined things, but he doesn't care. It's not like Steve hits him or anything. It's just sex.

And that's what he reminds himself when he tenses up because everyone's off doing their own thing and Steve and he are alone for the whole night. It's just sex. It's just sex, he reminds himself when he flinches because Steve puts a hand on his shoulder. It's just sex, he reminds himself when he freezes up because Jarvis tells him Captain Rogers is looking for him.

'Let him in, Jarvis,' Tony says, because this is all Jan's fault. He was doing fine until she butted in and he won't let her destroy this.

'Are you quite certain, sir? Your heart rate is climbing.'

It's stupid to feel angry at his own AI, but he does. He can't deny Jarvis' observation, can't pretend his heart isn't beating a little quicker at the prospect of facing an accusing Steve and trying to justify the importance of the project he's been working on, without sounding like he's making excuses for ignoring him. 'Yes, Jarvis,' he says through gritted teeth, 'I'm certain.'

Steve wanders into the lab and staggers over to Tony. He's all decked out in the Captain America uniform, to Tony's bemusement. But something's not right. The uniform is tattered and torn and Steve looks haggard, little cuts are scattered across his face and hands, like he's been involved in a scuffle. But that's not right; he's been in the mansion all night. 'Steve?' Tony asks cautiously. 'What happened?'

Steve steps closer. 'Tony,' he says and it sounds worn-down, dejected and totally un-Cap-like. 'He's a Skrull, Tony - an alien. He's not me.'

That's when Steve walks in. The real Steve. He tackles the uniform clad Steve to the floor and they fight while Tony looks on trying to figure out if this is real or some sort of bizarre dream. 'Jarvis! Prep the mark V,' Tony says after his brain snaps back into gear. He's not sure who, or what, this new Cap is, but he needs to be prepared in case the real Steve can't handle him.

By the time Tony returns, the imposter Cap is holding the unconscious Steve in a headlock. Tony aims a repulsor at him. 'Let him go.'

'Tony, wait, please.' Tony doesn't shoot. But only because the fake Cap might try to break the real ones neck as he goes down. 'You have to listen to me, Tony.'

'I don't have to do anything. Let Cap go.'

'I am Captain America!'

Tony laughs. 'I saw Steve half an hour ago. You expect me to believe you changed into your uniform and then he,' Tony tilts his head to the unconscious Steve, 'beat you up and stole your clothes?'

The imposter shakes his head. 'Tony… I've been gone for a long time. Over a month.'

'Oh this shit just gets better and better.'

'Tony, listen to me! You think this is more absurd than being frozen in the Arctic for seventy year?'

Tony scowls. He steps closer still pointing the repulsor at the imposter. He stares this strange definitely-not-Captain-America in the face, leans closer and plucks out one of his hairs. The Cap-clone yelps. 'What was that for?'

Tony quickly backs away, better to keep his distance until he knows what he's dealing with. 'Analysis.' He sticks the hair under a scanner on his worktop without turning his back to the Cap-clone. 'Jarvis, run a full breakdown on that for me. Tell me who - or what - this joker is.'

'Right away, sir.'

There's a tense moment of silence before Jarvis answers his request to tell him it's 'Captain Steven Rogers.' Tony sighs. 'Run the goddamn scan again, Jarvis.'

'Sir, I don't think that will be necessary.' He should not have to argue with his own AI, who should not be stupid enough to refuses to acknowledge the possibility of an error, despite the fact that the real Steve is standing five feet away in clear view.

'Run the fucking scan before I programme that defiance out of you, Jarvis.'

'Sir, in conjunction with your previous request, I took the liberty of running scans on a recent sample of Captain Rogers' blood.'

'And?'

'It appears… Captain Rogers' DNA contains aspects of unknown origin, likely alien.'

'That's not helpful, Jarvis. Which Captain Rogers?'

There's a pause. 'In the civilian clothing, Sir.' Jarvis sounds almost apologetic and it takes Tony a full three seconds to realise why. That's his Steve. The real Steve.

'He's a Skrull, Tony. I was captured over a month ago. He's been impersonating me since we returned from the fight with Loki.'

He wants to say no. It can't be right. It has to be a lie. Jarvis has to be wrong. But it's not and he's not. And oh fuck. It takes exactly six seconds for the implications to hit Tony, but when they do it's like nothing he's ever felt before. He freezes, utterly still with horror for another three seconds before he doubles over clutching his stomach and vomiting all over his thousand dollar shoes. For thirty-three seconds he heaves and heaves as though there's something in his stomach that's causing this and if he can just vomit hard enough it'll all go away.

From the corner of his eye he sees Cap, Steve, the real Steve, the not-a-Skrull-Steve, lower the unconscious Skrull-Steve to the floor and take a cautious step closer, hand outstretched. He's saying something, Tony's pretty sure, but he can't hear him. He can only hear the overwhelming pounding of his heart beating far too fast (like that day in the training room. Oh god, like that day in the training room).

He thinks about all the things he did with Steve. Not Steve. The things… he thinks about all the things he did with Not-Steve and with a moment of total clarity he wishes Loki had killed him, because it makes him feel so overwhelmingly wrong inside. He pictures himself happily sucking off Not-Steve. And shit, he's vomiting again, like it's not already far too late to get it out. Like it's not inside him right now, twisting around inside his intestines somewhere, permanently tainting him with something Not-Steve.

He stumbles back, away from Steve's outstretched hand, because… if he knew. If Steve knew. He'd hate him. Tony Stark, so desperate to fuck Captain America that he didn't even realise there was no way the real Cap would do those things with him.

His eyes are blurring, and he's pretty sure it's because he's crying. And isn't that just pathetic? The whore who sleeps with a Skrull and cries about it afterwards. He realises dimly that he's struggling to breathe. Having a panic attack, something in the back of him mind tells him vaguely. He should probably try to calm down. But fuck that, he will never be calm again, because he's had sex with a fucking alien. His vision fades, his legs fold beneath him and he's pitching forward into his own vomit.