Well, he got into street fights all the time in high school while he was still in Oregon. So, he certainly would enjoy signing up for a fight club.

He's also pretty relaxed about fighting, he finds it therapeutic. So, as long as the guy he's kicking ass with is pretty decent and good humoured about the whole thing, he's pretty likely to make friends with them. It's always nice to have a sparring partner who isn't a whiner.