JUKF-067 — My Brother Is My Onapetu Nonoka-Chan Nonoka Sato

Nonoka, a girl who is more interested in sex than studying, has a brother who failed the entrance exams three times and stays at home all the time, peeping on his sister masturbating or having sex with her boyfriend. One day, the perverted brother sneaks into Nonoka's room and fails to seduce her every night. From that day on, the balance of power is reversed and the foolish brother becomes a servant, and his sister starts treating him like a butter dog on a daily basis. They're both to blame, but this brother and this sister are just like the others.