Saotome is a short first-year high school student who is poor at sports and struggling with his grades. He had always believed that studying was his only strong point, but at his new school his academic performance is far from impressive, leaving him feeling that he has nothing to offer. One day, the school's perfect student council president, Kawaibara-senpai, approaches him. She is academically brilliant, athletic, elegant, and beautiful, and has maintained the top rank in her grade since enrolling. She offers to tutor Saotome after school, but she attaches a peculiar condition: he must wear a sailor-style female uniform during their study sessions. This request is linked to a secret she has never told anyone—a secret that embarrasses her but also drives her fascination with cute things. Reluctantly, Saotome agrees, and their secret after-school sessions begin.

The story follows the developing relationship between the earnest but insecure Saotome and the outwardly perfect but secretly obsessed Kawaibara. Saotome is constantly subjected to Kawaibara's overwhelming "cute harassment," as she dresses him up in various outfits, takes photos, and showers him with attention. Despite the absurd situation, a genuine bond forms between them, blending comedy, romantic tension, and heartfelt moments. The narrative arcs revolve around the two navigating their unconventional arrangement, the growing mutual affection, and the challenges of keeping their secret from the rest of the school. The manga is a lighthearted romantic comedy with a focus on dress-up antics and the dynamic of an older female lead who is deeply infatuated with her younger male underclassman.