Marika Uruuno cherishes the idea of a conventional life filled with love, marriage, and family. However, her world is turned upside down when she catches her best friends sharing a kiss, a behavior they have never exhibited before. To her surprise, she soon discovers that her all-girls school has transformed overnight, leaving her in a reality where men are nowhere to be found. In a state of shock, Marika seeks solace in the nurse's office, where she encounters Lily Kazami engrossed in a book about parallel universes. Despite initial skepticism, Marika confides in Lily about her strange predicament. In an unexpected turn of events, Lily offers her help under the condition that they go on a date together. Will Marika adapt to this extraordinary world devoid of men, and can Lily aid her in finding a way back to normalcy?