Hachimitsu Private Academy, once an all-girls boarding school, finally opened its doors for boys to enroll.
Only five guys manage to make the cut into the elite boarding school: Kiyoshi Fujino, our main character, Takehito "Gakuto" Morokuzu, the smart one, Reiji "Andrei" Andou, the fat and strong one, Jouji "Jo" Nezu, the mysterious hood-wearing one with non-fatal severe stomatitis, and Shingo Wakamoto, the American one. But these five guys have only one thing on their mind: getting a girl.
While the other four guys are down on their luck, Kiyoshi befriends his female classmate, Chiyo Kurihara, whom is obsessed with sumo westling. Seizing his opportunity, the two decide to go see a sumo fight together.
Later that night, the guys decide to peep on the girls while they change. But they quickly get caught by the "Official Underground Student Council." Made up of Hana Midorikawa, the secretary, Meiko Shiraki, vice-president, and Mari Kurihara, president and daughter of Chairman Kurihara. The council enforces the school's laws with strict disciplinary measures, such as locking all five guys into a prison in the middle of the school. Except... the harsh treatment backfires as the guys seem to love being beaten by a hot chick.
Meanwhile, Kiyoshi is determined to break out and keep his promise to Chiyo, though he manages to get himself in trouble by accidentally seeing Hana relieve herself.