Kyoko runs a calligraphy class, satisfying her desires through time spent with her students. However, her lust grows stronger each day, and she eventually crosses the line by seducing one of her pupils. Yoshino, who teaches shakuhachi, uses her past experience as an instructor to gather students and run her own class, but the activities taking place there go far beyond imagination. Meanwhile, Mizuki teaches men's kimono dressing at a traditional attire school, wearing only a fundoshi instead of underwear—a choice hiding a secret deeply tied to her own desires. Each classroom harbors intense, hidden dramas lurking beneath the teacher-student relationship.