Yamato is the daughter of one of the Four Emperors of the Sea, Kaido, and ruler of Wano Country, from the One Piece series. Growing up, she idolized a legendary samurai warrior named Kozuki Oden, and even decided to become like him, impersonating Oden and adopting his mannerisms 20 years after his death, much to her father's disapproval. Whilst she is a female, she however refers herself as a male.