Steve Rogers had never questioned his sexual orientation. He was born in a time of suppressed expression and raised to be a chivalrous gentleman to women, a hero against bullies, and a friend to men. So, while he had been already over come with the explosion of technology in the time he had been sleeping, he was even more shocked (and embarrassed) when it came to modernly acceptable behavior. Women's bodies revealed in commonplace pictures, vulgar language frequenting people's vocabulary, and people acting on their own emotions without much fear of social reputation. Couples of mixed races and sexualities, people called feminists, and the concept of multiple genders. The world had become a very different place in the time he'd been gone, and while he had yet to decide he didn't like it, he was also unsure he did—all these new revelations and identities shoved in front of a man who had thought "fondue" meant sex.
And then there was Tony Stark; a man so undoubtedly aware of himself it was almost a surprise. Almost. Tony Stark stopped questioning his sexuality when he turned twelve—at which point, he (and his very vocal genitals) decided, he was going to sleep with whoever damn well he pleased. He walked through life never questioning whom he couldn't sleep with, or how appropriate it was—all Tony Stark needed was a few drinks and verbal consent—and it was game on! Tony's only rule was that he wouldn't sleep with anyone any more drunk than he was. He did what he wanted, when he wanted, with whom he wanted, and only with people who wanted him (not that finding anyone was ever a problem). To Tony, sex was a game and love was just a thing he didn't quite have time for right now—but yes, Pepper, schedule it for next month! Tony had few boundaries, and chose only to respect other another person's at all if they let him dance a few feet past the line. So, with these things factored in together, it should have been no surprise to anybody that, upon meeting each other, their friendship refused to grow—their words to each other acting more as a pesticide than as a watering can.
But, at the sarcastic suggestion of both Agent Coulson and Director Fury, the two had gone out drinking. It was no good having a team of geniuses and ass kickers if they were constantly clashing with each other, and while the Avengers had managed to work as a cohesive team against Loki, there was no guarantee that without some serious bonding they could ever be anything stable or reliable. Given their different personalities, pasts, and abilities, the team seemed to be getting on much better in comparison to their breakdown on the SHIELD aircraft. However, they all knew that their progress would amount to nothing if they couldn't get their two alpha males to coincide with each other.
So the two had gone out drinking. The location was, naturally, Tony's suggestion, and Cap wasn't surprised. Annoyed, yes, but not surprised. He agreed to go, his better judgement at odds with itself. He knew he was going to have to learn to get along with Tony eventually, but he'd had a long day and if he could put if off, he wanted to. But in the end his better angel won out, Completely unprepared for Tony's date jokes and airy flirting, Steve was made immediately uncomfortable.
"Relax, Capsicle. You're making me regret letting the agents set us up," Tony said lightheartedly, as both a slight apology and a chance to politely reject the advances. "You're so cold sometimes I wonder if your insides have even defrosted yet." He muttered in a far-away tone as he ordered a scotch.
Cap sighed. "Look, Tony, could you not do this right now?" He leaned forward, massaging his temples with his fingertips. "I don't even drink." His brain was already shutting down. He was tired, he'd had a long day, and he was overly stressed. His better angel was wrong; today wasn't the day to make nice with Tony Stark. Today was a day to go home, go to bed, and sleep off all his emotions.
"You do today," Stark said, and he called for a second scotch to be placed in front of Steve.
"Stark, I don't-"
"Cap, it's just a scotch. It's not going to kill you." Cap gave him a no-nonsense look, and Tony cut him off before he could talk. "Cap, one drink. You can't get drunk anyways! What difference does it make?" And when Cap looked surprised, Tony immediately explained. "I own you, Cap. We may not have your super-serum but nobody knows your body better than I do." he downed his scotch and laughed. "So trust me, it won't kill you."
Steve nodded, and looked down at his glass before tentatively reaching for and downing it. He made a face. "Why do you drink this stuff?"
"Why does anybody do anything?" he shrugged as the barmen refilled his glass. "This is boring. I'm bored. Let's go home." he said suddenly, and Steve looked at him in surprise. "I can drink at home." He slapped some cash down on the counter.
Tony drove them back (Steve's bike was back at the mansion, and Hogan was off). It was quiet; Natasha and Clint were on a mission, and everyone else was asleep. Walking in, Steve immediately started for his room.
"Where do you think you're going?" Tony asked. "We have stuff to talk about. We came home so we could talk, not so you could lazy off to bed."
Steve turned and looked at him unhappily. "I'm tired, Stark."
"Jarvis, lock down Captain Roger's room until further notice."
"Locked down, sir,"
Steve looked at Tony in disbelief, his face tired and resistant. "Tony, come on. This isn't funny."
"I agree," Tony shrugged simply. Steve looked ready to get angry. "Cap, look. The way I see it, New York and pretty much the whole earth is counting on us, and if we fail because you and I were too tired to work out the kinks of our leadership methods, it's then you gotta think; this is a pretty pathetic team. This isn't just a joke to me, Rogers. Us not getting along is literally the end of the world."
Steve looked at him straight in the eyes, trying to judge whether or not he was being serious, before he sighed, his nice guy letting through.
"Okay, Stark. So, how exactly do guys go about being friends in this day and age?"