The Joryu-kai was a Japanese martial arts group that was founded by Kazuma Kiryu (alias "Joryu") in 2019 with the goal of competing in the Castle's "Team Hell Rumble" battles. The Joryu-kai initially included Kiryu, Businessman Taro, Hammerhead, Hattori the Ninja, and Phoeniki, but Kiryu came to recruit Dotonbori's gang leaders and several other fighters into his ranks.