Shizune Mejiro, heir to the influential Mejiro family, navigates a high-stakes rivalry between the Kin'gyoku and Ōgyoku academies as Kin'gyoku’s Student Council President. Publicly, he masquerades as a frail, beloved figure, his long black hair and dark eyeshadow accentuating a polished facade that belies his cunning. Privately, he employs whip mastery and covert martial arts training to undermine Ōgyoku, strategically exploiting allies—including manipulating the protagonist into athletic competitions—to advance his family’s quest for dominance.

His schemes, from bribing peers with gourmet incentives to orchestrating sabotage, often spiral beyond control, inadvertently sparking schoolwide ninja fervor. Tensions with Ōgyoku’s Shuu Maejima erupt into reckless showdowns, such as a sabotaged motorbike race that shifts their feud from shadow games to open hostility. Criminal alliances and political maneuvers to dismantle regional school unions further blur the lines between academic rivalry and underworld warfare.

A mistaken-identity injury during an ambush fuels his vendetta, while exposure of his machinations by a peer fractures his composure, though he doubles down on Kin'gyoku’s supremacy. The climax pits his meticulously planned assault against Ōgyoku amid external disruptions and shifting loyalties, underscoring his entanglement of personal ambition and dynastic legacy. Childhood bonds fractured by rivalry and his obliviousness to romantic overtures from subordinates underscore the isolation beneath his strategic brilliance, framing a conflict where familial obligation clashes with the ethics of power.