Shy and innocent beautiful girl Mahiro transfers to a new school, only to discover a disturbing system known as "Duty as the 'Convenience Store Girl'"—a program where female students are forced to serve as sexual outlets for male students. Mahiro watches in terror as her classmates are selected one by one, brutally used and violated by their peers. Eventually, her turn arrives. Subjected to forced deep throat, repeated creampie after creampie, and relentless, punishing sex until her body breaks down, Mahiro slowly descends both mentally and physically into the role of a "convenience girl." Her humiliation and tragedy unfold in full detail.