Knew him enough to know he's acting weird?

[At least that sure seems like the case. Arthur picks a locker and strips down, tossing his clothes in willy nilly - not a ton of concern for modesty here, either. He...wears a lot of layers, in the day to day. So he might be even thinner than he looks. He also wears long pants and sleeves all the time, so good job seeing more skin than he usually shows.]

Yeah, kinda! I mean, Raquna has 'em, but she's basically a princess. And plate armor's no good for swimming in.