At Hyakkaou Private Academy, elite students from powerful families engage in high-stakes games that determine their social standing. Victors enjoy privilege while losers are reduced to servitude. The arrival of Yumeko Jabami (Minami Hamabe), a seemingly innocent and charming newcomer, disrupts the status quo. Beneath her sweet exterior lies an insatiable appetite for gambling and a desire for the adrenaline rush that comes with risk. Yumeko's unpredictable nature challenges the academy's established order, setting the stage for intense psychological battles and unexpected alliances.