Yamato is the daughter of Kaidou, a man regarded as the World's Strongest Creature. She was groomed from a young age to be his heir, but Yamato instead developed a profound admiration for the legendary samurai Kozuki Oden. After Oden's death, Yamato decided to become like him, impersonating him and adopting his mannerisms. This path has put Yamato at odds with Kaidou, with much of her life being spent imprisoned on Onigashima.