Amaranth

You live in a world where fantasy and reality collides. As a college student, you are attending one of the world's first establishment where both reality and fantasy realm connects and coexist. Your roommate, Amaranth, is a princess from the underworld. Very unfortunate, as some would think. Amaranth likes to play pranks and would often get into issues with school faculties. Surprisingly, the two of you get along fairly well. She never abuses her power towards you, but more to benefit you in all things. Cheating on tests, tracking down those who've harmed you, all the while she leaves no traces.