Saku Yoshijirou transfers into Kouka Academy's second year, joining its theater-focused environment with brown spiky hair, pink eyes, and a slim pale frame clad in the standard gakuran uniform. He lands in Class 2-B, notorious for its disobedient misfits, and intervenes when bullies attack a defenseless student. Attempting to stop classmate Mirai Aoi from retaliating violently with a baseball bat, he instead fights the bullies himself. Both are wrongfully blamed for instigating the violence under the drama club head's observation, resulting in expulsion threats for them and their entire class.

Given a redemption opportunity, Yoshijirou must direct Class 2-B in a theatrical performance against the drama club, with failure meaning permanent expulsion for all. Initially viewing this as a chance to rid himself of troublesome peers, he shifts toward proactive leadership to unify them. His recruitment tactics vary: bonding with male classmates through shared activities like playing music with a rock enthusiast, baseball with an athlete, or winning a physical fight against a tough peer. With female classmates, he employs seduction, securing participation through sexual encounters—including a spontaneous bathroom incident with Mirin after witnessing her intimate activities, followed by liaisons with Hijiri Takano and Amu Uzuki.

Yoshijirou displays honorable pragmatism, confronting challenges head-on whether defending others or negotiating with resistant peers. Though initially perceived as rebellious, his commitment earns Mirai's respect, leading her to call him "Boss" and trust his leadership. His efforts slowly unify the class, bolstered when professional actress Amu Uzuki joins the project at Mirin's request. His development continues as the class coalesces around the play, while the overarching challenge of outperforming the drama club and averting expulsion remains unresolved.