Love Apartment Opposite

No regrets for your youth; In order to give yourself a happy ending; I, an outsider who has traveled through time, want to fulfill a dream for my youth ps: I update it twice a week, so I usually take the time to code. CP appears in the later part, and the protagonist is assumed to be a straight-type warm man; the protagonist has only watched the first four movies. Pps: updated once a week Intention: Let nature take its course, don't force it