Aoi Satsuki enrolls at Paradigm, an all-girls Christian school, with the intention of having a high-class and pure experience as a young adult. However, what she discovers behind the walls of her new school is the exact opposite. On her first day, she witnesses Rin "Riri" Senjou confess her love to a girl, only to be rejected. Aoi comes to her rescue with a handkerchief to wipe away her tears—and when Riri reveals her wish to find a cute girlfriend to enact her unchaste desires with, Aoi realizes that Paradigm may be a far cry from pristine.

Despite Riri's improper and erratic nature, she and Aoi quickly become friends. Riri's frantic search for a girlfriend makes Aoi reflect on her own lack of romantic aspirations. As Aoi promises her new best friend that she will not abandon her for a boy, the two girls grow closer in ways that Aoi could never have anticipated.

[Written by MAL Rewrite]