Kimito Kagurazaka, a regular guy with a unique interest in muscular men, finds himself entangled in a web of lies at the prestigious Seikain Academy, an all-girls school. Mistaken for a man-loving individual, Kimito becomes the school's 'commoner sample' to bridge the gap between their sheltered world and reality. Forced to pretend to fit their expectations or face severe consequences, including the threat of losing his manhood, Kimito navigates a quirky cast of characters complicating his already tumultuous life. Aika Tenkuubashi, an outspoken outsider; Hakua Shiodome, a brilliant young mind; Karen Jinryou, a samurai's daughter fixated on besting Kimito; and Reiko Arisugawa, an ideal student envisioning a future with Kimito, form the Commoner Club alongside him. Together, they strive to broaden the girls' perspectives beyond academia while Kimito unravels the mysteries of his peculiar companions.