The manager was friendly, but i felt the interview process asked too little questions vital to the position itself. I felt like they were doing this interview out of neccesity more than they were actually interested in hiring me.

For a part time job, they normally want to know if you are capable to do the work, days of week you are available and what time you can start and leave work. Also some other basic things about you locomotive method and if it's train or bus, what is the name of the nearest station/bus stop from where you live, and also, how much money and time does it cost. In my case, the main manager did the interview, so he already accepted me in the end of it (because normally in japan they normally say you'll receive a phone call just if you are accepted within a week).