Ever since she was old enough to understand, Mariko has only ever loved women. One day, she falls in Kokoro with Rinriko, the wife of the Kinoshita family, who comes to her as a house sitter. Because she is an employee, she thinks of Rinriko and indulges in masturbation every day. However, Rinriko, who senses Mariko's base feelings, shows off her voluptuous body to Mariko, as if mocking her innocent feelings... Mariko, with her emotions running wild, devours Rinriko's body. Rinriko enjoys the sight with a smile of pleasure on her face...