While here I decided to stay for another term. I didn’t apply for a long-term visa, though. Can I extend my stay?

Some students manage this by traveling for a few days to a nearby Asian country and then re-entering Japan, which gives them a new 90-day stay deadline. KCP has not had any students who were refused re-entry, but re-entry is at the discretion of Immigration authorities.

It’s much better to make the decision well before you leave for Japan, so that KCP-Japan can help you obtain a student visa.