Genres: Seinen , Drama , Psychological , Thriller , Crime , High School , Romance , Shoujo , Revenge
Description:
Ogino, a high school teacher, is persecuted by the students of her homeroom class, who call her "sludge". The only place where Ogino can be an ideal teacher is in the letters she writes to a truant girl named Yoran. One morning, she receives a reply to her letter from Yoran!