Mariko was abandoned by her parents and raised in an institution from the time she was born. - She is fed up with her relationship with her homeroom teacher who selfishly engages in sex without sex, and stops going to school. - One day, he bumps into his homeroom teacher by chance on the street and runs away as fast as he can. - He escapes by arriving at an old house where a middle-aged man with gray hair lives alone, but in exchange for hiding there for several days, he is once again asked for sex. - This is the story of a lonely female student who goes through her adolescence only to be used as a toy by men.