Kazuya can't contain his joy when he hears that his mother's friend Umi, who taught him how to study when he was a student, is returning home after a long time.When I met Umi again, she became more beautiful than before.Even now, Kazuya's secret feelings for her continue to grow, and he has a relationship with her.Kazuya, who has lost her control, continues to be swept away by her lust and asks for her infatuation.However, she says that such an extraordinary relationship cannot continue.