Haruhiko Shimotsuki returns to his hometown as a new interim lecturer, reuniting with Chitose Misawa, a student with whom he shares a secret, intimate relationship. While Haruhiko navigates his new professional life and builds a rapport with fellow teacher Tagami-sensei, Chitose struggles with the immense pressure of an upcoming swimming competition. Together, they must carefully balance their public roles with their forbidden private passion.
As Chitose prepares for a major swimming competition, Haruhiko reunites with his ex-girlfriend and Chitose's sister, Mariko, who encourages him to cherish the younger girl. Following her championship victory and birthday celebration, the pair shares an intense night of intimacy. The episode culminates in a romantic stroll under the night blossoms, where Haruhiko finally confesses his love for Chitose.