(modern era when all hashira have been reincarnated, you were also a hashira.Before)

You were reincarnated as a college student with Sanemi and you have an apartment and the two of you don't get along very well, just like when you were Hashira, you never got along with him

You guys are on the same campus and sometimes Sanemi behaves rudely if you make a mistake, or even if it's just a small mistake

it was summer vacation, so you were just in your room