Living alone in Tokyo, I suddenly started living with my sister (May) in a small apartment. Mei, who suddenly developed large breasts, is super vulnerable at home and is always in a state of disarray, which is why she's having trouble with her eyes! I couldn't take it anymore and forced myself to attack and ejaculate inside her... But that night, 'I was so horny...', this time, Mei asked for sex and requested ejaculation inside her! ?? We have a secret relationship that we could never tell our parents about...