The Ishioda-gumi was a Japanese yakuza family that was affiliated with the Omi Alliance and its Tokyo Omi Alliance splintergroup. The family was led by Reiji Ishioda during the late 2010s, and it took advantage of Governor Ryo Aoki's Kabukicho 3K Plan to expand into Kabukicho, Tokyo. The family became one of the most powerful clans within the Omi, rivaled only by the Watase-gumi, Ryudo-kai, and the Arakawa-gumi. In 2019, the family invaded Yokohama to capture the Geomijul's money counterfeiting facility, but the Geomijul destroyed their own machines as Ichiban Kasuga and his friends held off the Omi invaders. The Ishioda-gumi later allied with the Yokohama Liumang for a second attempt at taking over Yokohama, but Mabuchi's planned takeover failed, resulting in his banishment by Tianyou Zhao. Following the dissolution of the Omi Alliance, the Ishioda-gumi joined with Yosuke Tendo of the Ryudo-kai and Jo Sawashiro of the Arakawa-gumi to form a new Tokyo Omi Alliance. The Ishioda-gumi failed to assassinate Sawashiro before he could testify against Aoki, and Ishioda was killed in a Ryudo-kai bombing soon after, causing his family to disband.