Antagonist

" 'I thought he was going to be sick. You weren't bored, were you, Robert?' (pg 169)"

Mike could be sen as an antagonist here. Several times, he teases Robert rather cruelly about an assortment of things. Earlier in the novel, he gets on Robert for having a thing for Brett even though, at this point, it is safe to say that they all seem to share that in common. Here, he is gives Robert a hard time for a statement he had made earlier on in the novel. Robert had said he was afraid he would be bored during the bullfights and everyone there had held it against him. Realistically, no one really likes Robert, but it is just one of those things no one is supposed to say. It is like the well-hidden elephant in the room. Mike basically says everything the rest of the group is thinking but too polite to say. Hemingway adds Mike to the story to add drama. Mike's teasing brings out a bad side of Robert that is somewhat like his old self. He really doesn't say anything or stand up for himself, much like he never stood up for himself with Frances.