Taking risks is a part of human nature, and to gamble means to risk losing something important in the pursuit of obtaining something greater. However, the world of gambling is neither welcoming nor forgiving, and some will lie and cheat to win. Therefore, a powerful organization, "Kakerou," exists to ensure that all bets maintain a semblance of fairness.

Baku Madarame, often referred to as "Usogui," is a genius gambler willing to bet more than just money. Putting his life on the line, he faces off against psychotic opponents in deadly psychological games. With his cold and calculating nature and high level of intellect, Baku challenges the liars known as gamblers while aiming to seize control over Kakerou itself.

Included one-shots:

Volumes 12–15: Igyou Tobakusha Usokui

Volume 25: Yakou-san