If you are still doing the au ask, maybe a concubine au?
Where’s that one post where the king’s concubines are basically his entire council ruling the country
Steve and Bucky are injured in battle--Bucky loses an arm, and Steve’s lung function has suffered. They can no longer fight, and Howard is disgusted that two of his best soldiers were bested, so in the most assholish move possible, he gives them to Tony as his concubines.
“Gross gross gross gross gross!” Tony wails when he finds them in his room, dressed in wispy lace and little else.
“Wow!” Steve and Bucky exclaim, offended.
Tony gives them a thunderous look that cows them immediately. “I’m sorry, was I supposed to be happy that I now apparently have sex slaves because my dad thinks you’re not people anymore just because you were ambushed and injured?!”
“Uh,” Steve and Bucky say, and then they try to apologize, but Tony is already storming out of his room, because he’s so hurt and angry and he has the propensity to cry when he’s angry.
Howard dies and Tony becomes king and he hates every minute of it. It figures that Howard would give him one final “fuck you” by leaving Tony a country at war. He’s coronated and everyone is hopeful for his reign and so he smiles and gladhands like his mother taught him to--and then when he gets back to his room, he screams and cries in rage.
“Holy shit,” Bucky says, and Tony yelps and falls over, because he hadn’t realized they were there.
“What the fuck are you two doing here?!” he hisses, scrubbing at his cheeks even though he knows the damage is done.
“We were told we should come up. Something about ‘kingly virility’ and ‘working off stress,’” Steve replies, pouring on the sarcasm heavily.
“Well I don’t want to fuck you so you can fuck off back to wherever concubines live,” Tony snaps.
“Doll, lie down and let Stevie give you a back rub,” Bucky sighs, rolling his eyes. “You look like you’re made out of a brick wall. If you go to sleep like this, you’ll be stiff.”
Tony glares at them, sniffing, then says, “I’m lying down because I want to, not because you told me to,” and they roll their eyes fondly as Tony does just as he said. “Ooh,” he mewls, whimpering, at the first firm press from Steve’s hands. “That hurts!”
“Your highness, please don’t be offended, but this is the most fucked-up back I’ve ever seen,” Steve says. “It’s gonna hurt.”
“Stop!” Tony mewls. “Steve stop it hurts, it hurts-!”
“It’ll hurt more tomorrow if I don’t do this,” Steve says, actually feeling pretty apologetic.
Bucky flops down beside him. “I’ve got an idea,” he tells Tony. “But you have to promise not to be mad first.”
Tony frowns at him. “No.”
“Well I’m a liar and I’m gonna tell you the idea anyway,” Bucky declares. “I think that you should let us give you a deep tissue massage. With our dicks.”
Tony glares at him, aghast, too appalled to speak.
“That way you’ll be all fucked-out and relaxed and Steve can rub your back properly,” Bucky continues, ignoring his offense. “Come on, sweetheart, even I can see your back is fucked up, and I haven’t even touched it.”
“Well,” Tony snaps, and then sags with a whimper because oh God he really is tense. “Fine, but I’m not going to enjoy it,” he says mulishly.
They don’t get around to rubbing his back until he actually passes out after his third orgasm, but perhaps it’s for the best, because, “Oh my God his back is really so fucked up I don’t know how he even managed to lie down.”
“Hello, I’m your new concubine,” Clint says, holding his hand out to shake.
Tony stares at him, offended. “What?”
“I mean, my old captain thought I’d turned and was selling information to the enemy, so the options were beheading or sexual slavery. So here I am!”
“Leave immediately,” Tony says, and sighs in frustration when Clint cheerfully ignores him to walk into his bedroom.
“Clint! Hey!” Steve says happily. “They make you a concubine too?”
Clint walks over to hug him. “Yeah, it’s real fashionable I guess!”
“I’m not letting him fuck me,” Tony says, crossing his arms and glaring at him. “I only let you two do it because you rub my back.”
“I’ll rub your feet,” Clint offers helpfully.
Tony, as it turns out, is a sucker for foot rubs, and also apparently for the trick Clint learned when he was seducing information out of the enemy’s prostitutes.
“Man, where have you been,” Bucky complains. “Steve and I had to take turns to get him that relaxed and you got him to come so hard his eyes crossed after one time!”
“It would be foolish to reveal my tricks,” Clint says as Steve climbs on top of Tony to rub his back while he’s passed out.
Natasha just appears one night.
“I’m almost entirely certain you were working for the enemy and are the cause of my father’s assassination,” Tony says, and then, “I didn’t consent to this and I would very much like you to get off of me.”
“Understandable, but I’m very disappointed because I’ve heard great things about your dick,” she says and climbs off of him.
As it turns out, Natasha had been a double agent and was the reason for many decisive wins on their side, but she’d been so deep under cover that no one trusted her anymore, and like Clint, it was the decision of death or sexual slavery.
“I’m abolishing sexual slavery and we’re having real, actual trials for people that are assumed to have done a crime and what the fuck are you doing,” Tony says as Natasha climbs back on top of him.
Natasha smirks and raises an eyebrow at him. “That’s really sexy of you, deciding to make sure there’s actual justice in your country instead of happily crushing people beneath your boot.”
“I’m having a lot of mixed feelings about this but the biggest and strangest feeling is fear,” Tony admits.
“I cause a lot of fear boners,” Natasha says, as simple as breathing, and leans down to press a kiss to his slack mouth. She leans back when he doesn’t respond and snorts when he just gapes up at her. “To be clear, I’m gonna ride your brains out now. If you say it’s okay,” she adds
With the abolishment of sexual slavery, it means that Tony can no longer have concubines.
“I’m not leaving,” Bucky declares. “I like your bed and you let me eat the plums out of your fruit salad. Also I like the way you look when we get you all fucked-out.”
“I’m staying too,” Steve says. “I like being the one in charge of rubbing your back, and carrying you to bed when you’re trying to work late. And Bucky’s right--you look great when you’re satisfied.”
“I love that you call him ‘satisfied,’” Clint tells Steve happily. “It sounds so sweet and cute!”
Steve frowns. “What’s the problem with that?”
“There is nothing sweet or cute about Tony after we’re finished with him,” Natasha says, amused. “He’s just sticky.”
“I’ll have you know that you don’t get to decide whether or not you’re concubines,” Tony insists. “Sexual slavery is abolished. There are no concubines anymore.”
They all pause to consider this. Finally, Clint decides, “So we’ll be your lovers instead.”
“What,” Tony says.
“I like the idea of that,” Natasha agrees. “I’ll even take one for the team and marry him so he can have legitimate heirs.”
“What,” Tony says again.
“Great! With all of us working together, we can keep Tony permanently ‘satisfied,’” Bucky adds, using finger quotes as he smirks at Steve.
“What,” Tony says for a third time, but they continue to ignore him as they plan out their lives, even about inviting a couple other fellow soldiers up because they have very good ideas about how the country should be run.
Tony says that’s only allowed if they can get Bruce to live in the royal quarters as well because he’s pretty sure his ass will never recover if they don’t. Somehow, they manage it.
“You can’t fuck me you’ll tear me in half,” Tony sputters when Thor shows up.
“That’s mean, Tony, Thor’s always been a very gentle lover,” Steve scolds.
“I thought you’d be taller,” Thor says.
“Oh, I see, they brought you up to keep me humble,” Tony says, and punches Thor directly in the nose. “Well now you know that that’s never happening!”
“Tony!” Clint scolds.
“This isn’t the turn off you probably meant it to be,” Thor tells Tony, amused, and Tony yelps as Thor picks him up and puts him on the bed.
Natasha pets his hair gently. “Don’t worry, Tony, we’ll take care of you.”
“Well,” Tony says mulishly. “You always have.”
Thor pauses. “...Usually people aren’t this angry when I’m about to fuck them.”
“This is normal,” Steve tells him hastily. “He pouts because he doesn’t like it when other people are right.”
“Ah, I know someone exactly like that,” Thor says.
“Are you gonna fuck me or what,” Tony snaps.
Thor smiles at him. “You are just adorable, aren’t you?”
“You’re not allowed to fuck me anymore,” Tony tells him, and then squeals when Thor folds him in half.
Basically, Tony was the concubine the whole time, he just didn’t know it.