Jigoro Kuwajima (桑くわ島じま 慈じ悟ご郎ろう, Kuwajima Jigorō?) is the man who trained Zenitsu Agatsuma and Kaigaku. He was formerly the Thunder Hashira (鳴なり柱ばしら, Nari Bashira?) in the Demon Slayer Corps. Jigoro had a steadfast devotion to his students and strict training. Despite his status as a strong mentor and experience as a previous Hashira, he had a soft spot and unwavering dedication towards raising the next generation of students.