I really don't know what is going on in this gif, Chris getting closer and Sebastian away, and his face at the end. He doesn't like Chris or he was feeling something else? More sexual kind of thing
I don't think it's sexual for Chris Helmsworth, he's just a boring hetero pretty sure. But that reaction from Sebastian Stan is so peculiar. It reminds me of one time he was on one of the Marvel press tours and the interviewer asked him and Anthony Mackie who the hottest Avenger was and Stan immediately said "Tony Stark" or RDJr. Yet they were supposed to be doing this on-going gag where he and Mackie lust after Black Widow and I just remember Stan being all awkward after that, I think literally saying "Why did I say that?". It's that skittishness that makes me double take.
I remember his ex, this beautiful lesser-known actress (Margarita?), was at one point shagging Ezra Miller when they weren't necessarily broken up. And there was some fashion show not long after where Stan and Miller are pretty friendly with each other. I always thought that was strange too.
I don't usually speculate like this, I kind of think actors in-the-closet don't put that much effort into concealing it but he has such bi energy and such freak energy.