Yonezu, a regular high school student, dates Hina Takigawa from an elite all-girls school. Initially reserved, Hina reveals hidden exhibitionist tendencies after six months when Yonezu secretly observes her public masturbation and urination in a park. Confronting her about these acts outside their conventional intimacy, he transitions from a typical boyfriend to an active collaborator in her fetishes. He initiates mutual public sexual activities, seeking relationship enrichment through shared adrenaline and risk. Their experimentation includes incorporating sex toys like vibrators and dildos.

In subsequent events, Yonezu adopts coercive tactics. He pressures Hina into urination displays despite her resistance, engineers encounters near residential buildings to escalate exposure risks beyond her comfort, and overrides her boundaries—forcing acts against her will. This strain culminates in Hina resisting his demands, asserting her limits, and imposing consequences for his violations.