Gambling, that is the reason for my existence (raison d'être). At the prestigious private Hyakkaou Academy, a class system exists. This school, ruled by the student council, is dominated by "gambling." Win, and it's heaven. Lose, and it's hell. In this twisted academy, the strong in gambling are envied, while the weak are subjected to humiliation. Into this academy, a girl transfers. Her name is Jabami Yumeko...