The Keihin Gang is a Japanese hangure gang that is active in the Kabukicho district of Tokyo. The Keihin-dōmei was founded as an alliance of four separate gangs led by the "Keihin Four", with the smallest of the four being led by Kenta Kasai (whose gangsters were mostly street ruffians and athletic wear), the third-largest being Renji Honda's gang (consisting of bodybuilders), the third faction being Kaito Sakakiba's sumo fighters, and the largest and most powerful being Matsuhisa Koga's gang of combat-trained, white-collar criminals. In 2018, the private detective Takayuki Yagami ran afoul of the Keihin Gang after defending his restauranteur friend Kim Won-soon from Kasai's thugs, who regularly harassed Korean immigrants. The Keihin Gang declared war on Yagami, but their inability to kill him led to civilians ceasing to fear them. The people of Kabukicho later helped Yagami evade the gang's manhunt, and the gang was forced to give up. After the gang lost its massive handgun smuggling operation, the Keihin Gang was forced out of Kabukicho, and the "Neo-Keihin Gang" regrouped in Isezakicho, Yokohama. The gang collaborated with Kotoko Itokura to create the largest black market on the dark web.