Hakui no imôto: Mubôbi na o-shiri(白衣の妹 無防備なお尻)

Eri lives alone in the house left by her father. Eri, who has decided to work at Fujimura Clinic as a happy nurse, looks like a nice adult man to the director, Mitsuo, and makes a nasty delusion during work. One night, when Eri returned home, her sister, Yoshie, was chilling wheat in her room. After leaving home for a long time, he says he came home after being thrown away by an adultery partner. During such days, Eri happens to meet her classmate Ayumi, but...