Kanji Aotsuki was a Japanese yakuza boss who was patriarch of the Omi Alliance's Kyokuso-gumi subsidiary during the 2010s. In 2019, his family's welfare theft racket was broken up by Dotonbori information broker Akame and her partner Kazuma Kiryu, causing Aotsuki to punish them by robbing the workshop of their associate Akira Mizorogi and selling his high-tech combat gadgets on the black market. Some of those gadgets were purchased by the "Four Kings of the Coliseum," who used them to gain an edge in combat. He later failed in his attempt to ambush and kill Kiryu while disguising himself as a homeless man, and, in the ensuing days, he hid out in a hostess club while his goons harassed Kiryu on the streets of Dotonbori. Kiryu later defeated the Four Kings, causing their leader Kiyoshi Ugajin to betray Aotsuki's hideout. Kiryu once again defeated Aotsuki and forced him to return all of Mizorogi's remaining stolen gadgets, pay for Mizorogi's medical costs, dissolve his family, and work for the Akame Network as an informant.