Children from influential families in politics and businesses attend the Hyakkaou Private Academy. There, the hierarchy are classified by a series of games. Students that win are on the ruling side and the ones who lose become slaves. One day, a mysterious girl, Yumeko Jabami, transfers to Hyakkaou. She looks pure and pretty, but she's actually a compulsive gambler and seeks out the thrill of taking calculated risks.
Minami Hamabe
Yumeko Jabami
Mahiro Takasugi
Ryota Suzui
Aoi Morikawa
Meari Saotome
Taishi Nakagawa
Kaede Manyuda
Yurika Nakamura
Sayaka Igarashi
Natsume Mito
Runa Yomozuki
Ruka Matsuda
Itsuki Sumeragi
Matsumoto Kiyo
Nanami Tsubomi
Natsumi Okamoto
Yuriko Nishinotoin
Yuma Yamoto
Jun Kiwatari
Miki Yanagi
Midari Ikishima
Onodera Akira
Nitobe Kyuu
Unaware of her new school's ways, transfer student Yumeko Jabami is offered a high-stakes game of rock-paper-scissors against her classmate, Mary.
Having lost her initial buy-in against Mary, Yumeko raises the stakes even higher by reburying into the match with an extremely large bet.
Student board member Itsuki challenges Yumeko to a game of pairs. Rumored to have never lost in this game, Itsuki lays a shrewed trap agaisnt her.
Desperate to regain her status in the school hierarchy, Mary duels student board member Yuriko in a game of "life or death" as Yumeko looks on.
Yumeko takes Yuriko on and taunts her as if she knows something about the trap Yuriko has laid against her.
After a monumental outcome, Yumeko receives a cryptic file form the student board. Meanwhile, a card game for those heavily in debt commences.
Yumeko and Mary pair up for a game of Indian poker against Kiwatari, the class bully known for manipulating others through fear and intimidation.
Although able to repay her losses, Yumeko chooses to remain in debt in order to qualify for an official match with the student board president.
Yumeko agrees to go up against the Beautification Committee Chair in an ESP card game involving Russian roulette.
A nervous Suzui serves as dealer for Yumeko's deadly duel with Midari. Meanwhile, student board member Manyuda summons Mary for a surprising proposal.