Kabamaru was orphaned at a young age and raised by his grandfather Saizō Igano, who trained Kabamaru and another young orphan, Hayate Kirino in the ninja arts. While Saizō took care of the two children, he was also a very strict teacher, punishing incompetence or disobedience with physical violence. The two children eventually tried to escape, with Hayate suggesting they split up. Kabamaru was recaptured, but he refused to reveal his friend’s whereabouts to Saizō. Hayate watched, hidden, and finally made the decision to take advantage of the opportunity and flee. This choice haunted him ever since.