Hirakawa Asahi wakes up from a sick day to discover that the world's sexual morals have been reversed. In this alternate society, women are the ones who openly pursue sexual relationships while men are expected to be reserved and inexperienced. Asahi tries to adjust to this new normal, but his life takes an unexpected turn when he walks in on his popular classmate Sotogahama Riria pleasuring herself in the classroom after school. The next day, Riria drags him to the infirmary and confronts him about what he saw. After Asahi's weak lie fails, Riria admits to her actions and bluntly asks him to let her have sex with him just once. This request throws Asahi into a complicated relationship with Riria, who is far more innocent than her gyaru appearance suggests. As their encounters become more frequent, Asahi struggles to navigate a romance that officially is not a romance at all.

The story later introduces Nishimeya Hinayo, the top student in the grade and a quiet literary girl. When Asahi needs to retake a test, he goes to Hinayo's house for tutoring and accidentally discovers a stash of explicit bondage manga on her bookshelf. Rather than being embarrassed, Hinayo confesses that she wants Asahi to discipline her like the characters in those manga, adding another layer to his already tangled situation. The series follows Asahi as he becomes entangled in increasingly intimate arrangements with multiple girls, each relationship built on the premise of being something other than a genuine boyfriend and girlfriend. The core conflict revolves around whether these physical relationships can develop into real emotional connections within a society that has turned traditional gender roles upside down.