From a quiet library to a school-wide nightmare: A platonic promise shattered by a teacher's blackmail

The story follows Miyuki Arisaka and her boyfriend, who bond over a shared interest in literature. The plot transitions into a drama involving a physical education teacher named Okazaki, who uses recorded footage of an incident in the library to influence the couple's relationship. The narrative explores the subsequent breakdown of their platonic agreement and the involvement of other characters within the school setting.