Prison School follows Hachimitsu Private Academy, a prestigious girls' boarding school on the outskirts of Tokyo that suddenly begins admitting boys under a new policy. With two hundred girls to only five boys, Kiyoshi, Gakuto, Shingo, Andre, and Jo are immediately isolated and unable to make a normal first impression. Hoping to get closer to their classmates, the boys set their sights on peeping into the girls' bath, but the plan is crushed by the ruthless Underground Student Council. As punishment, they are locked inside the school's prison and sentenced to a full month of hard labor and humiliation.
From there, Prison School turns the academy's strict hierarchy into a stage for absurd comedy, as the five boys struggle for freedom, friendship, and a very stubborn kind of perverted brotherhood. The series keeps returning to the same harsh rules, escalating punishments, and power games inside Hachimitsu Private Academy, where every small victory comes at a ridiculous cost. Even at its most outrageous, the show remains centered on the clash between the boys' desperation and the school's relentless discipline.
