As Mitsuki grew older, she became more interested in sex than studying. She stayed home all the time, and her delinquent brother, who was repeating a year of school, would sneak into her room to peek at her masturbating or having sex with her boyfriend. One day, as usual, her brother tried to sneak into Mitsuki's room for night● but failed. From that day on, their power dynamics reversed, and the brother became her servant, treated like livestock by his sister…
