Rengoku Kyojuro was a major supporting character of Demon Slayer Kimetsu no Yaiba and a major character in the Mugen Train Arc. Rengoku was greatly enthusiastic in regard to his duties as a Hashira, and often came across as cheerfully eccentric. While completing his last mission, Rengoku succumbed to Akaza, the Upper Rank Three demon, after initially almost defeating him. His death brought sadness to many but he died completely his job. He protected everyone on the Mugen train.