Takeshi tiene una madre y hermana que no son de sangre, sin embargo, esto no evita que la hermana sea muy unida con él, cosa que no pasa con su madre, quien obliga, por medio del chantaje, a su ‘hijo’ a tener sexo con ella en su habitación por las noches.
Takeshi’s mother, Shino, and sister, Shinobu, are not blood-related to Takeshi. Although Shinobu attaches herself to Takeshi, she seems to refuse her mother. Except for that, they are peaceful family at first glance. However, there’s a secret in this family. Takeshi is taken into Shino’s room at night, and he is forced to do sex with her ignoring his will. Because he doesn’t want Shinobu to look down on him knowing their relations, he has to obey.