In a fictional adult school role-play set during Japan's 20XX birthrate crisis, Kaguya Academy launches a government program that makes adult students practice romance and intimacy—including sex. Yumi Nijimura signs up expecting to pair with her handsome boyfriend for extra academic credit, only to learn that partners must come from the same class. Unable to withdraw after signing the consent form, she is paired with Takuya Kimoi, the awkward nerd she despises. Under an AI robot's supervision, they are made to kiss, perform oral sex, and have creampie sex.