I'm sorry you weren't on good terms with your teacher. It would've been nice to have been able to say goodbye or at least given them a little warning. Tamahome is good at protecting Miaka, so I think they'll be okay. As long as Miaka doesn't go and do something stupid like she has a tendency to do.
Huh now that is a strange thing indeed. No, I haven't met Alim yet. It might be a good bet to ask him if he knows what's going on around here.
Under normal circumstances, I wouldn't really support stealing. But in this case, I think it's okay since you're new to this place and food is a necessity to living. Replaced someone? Maybe that would explain the plastic card I found in my pocket with a name and information that wasn't mine. I think it could be related, it certainly couldn't be a coincidence!