[Ninastar]

^ It could have easily happened. Two young girls living together in a forigen country and then your best friend is murdered. You want to know who did it (as you would) and you'd think about anyone who did anything strange/creepy at the time.

maybe he was always staring at the girls? perhaps he said things that were a little strange?

there's loads of different reasons. You'd be so exhausted that you wouldn't know what to think.