After divorcing due to her lesbian experiences, Sayuri works at a hospital before becoming an independent sex counselor. Mari, a nurse who had lived a life away from lesbian relationships since graduating nursing school, begins working as Sayuri's assistant and is gradually drawn back into the allure of lesbianism. One day, Hikari, troubled by issues in her sex life with her husband, visits the clinic. Sayuri reveals to her that she has latent lesbian tendencies, guiding the confused Hikari and awakening her curiosity toward lesbian relationships. Meanwhile, Mari secretly seduces Hikari as well. Eventually, Sayuri and Mari draw Hikari into a threesome lesbian relationship, forging a new bond between them.