"I'm sure we'll make a lovely couple," Clint said, and forced a smile. "Honey."

So, Captain America effectively manages to cockblock Tony for a year. It's not Steve's fault. Well, actually, it is. But he was just proving a point - that if a superhero is gay, how can it be wrong? Steve just picked the wrong superhero to make the point with. Now America will think they're dating - and Tony's not going to be the guy to break Captain America's heart. There's only one way out. To save face, Steve and Tony have to become fake boyfriends. Steve thinks the "boyfriends" bit will be the hardest to act... but maybe it's the "fake" part that will be the hardest act of all...

“It's a contingency plan in case of accidental teenagering,” says Stark.

The press seems to think Tony and Steve are in a relationship, and so many people seem so happy about it that Steve just runs with it, dragging Tony along. To a Pride rally. Whoever gave Steve that flag he's wrapped himself in deserves a medal.