that's exactly what i was thinking, his behaviour changing that rapidly sounds bad.
thing is, our campus is small, so dorms are on the uni grounds itself, and right next to each other. they see each other every day.
personally, i think she's just latching onto him as well, as she was cheated on in her last relationship, and she claims to already be in love with him.
either way, i've told her as much. let's see what happens. i've also made her promise that if he does anything physical she will report it. she said she doesn't want to cause trouble or hurt anyone's feelings, to which i told her to forget about others, and to think of her own feelings. so i'll help her with it if needed, but yeah. (there isn't any immediate threat, but this guy used to do drugs, and i'm getting a pretty bad vibe. i'll keep a close eye on it.)
let's see what happens.