Ruri is a physical education teacher at a private school and the advisor of the rhythmic gymnastics club. A member of the rhythmic gymnastics club whom she is dating brings up breaking up... Ruri agrees to the break-up, but makes a trade-off. The condition is that Maika, who recently transferred to the school, must join the rhythmic gymnastics club. After Maika joins the rhythmic gymnastics club, Ruri begins private lessons. Maika thinks of Ruri as a dedicated and kind teacher, but at the same time, she is attracted to Ruri's beauty and figure. Maika transfers schools a lot, so she never makes a single friend. Ruri treats her kindly, and she begins to seek something beyond a teacher-student relationship...