Ieyasu had short, somewhat unruly, dark brown hair and brown eyes. He wore a white martial arts headband.
He was a very cheerful boy who had hoped to become famous someday. His friends noted that his carelessness and lack of common sense would have gotten him killed instead.
He set out with Tatsumi and Sayo to earn money for their village. On the way, they were attacked by night bandits and got separated. Ieyasu managed to stay with Sayo while Tatsumi was separated from them.
He and Sayo were then invited by Aria to her mansion, and she provided them with a meal that was drugged, making them lose consciousness. He was tortured by Aria's family and in the process was infected with the Lubora disease, an incurable virus that slowly kills its victim.
Tatsumi and Night Raid arrived at the place where he, Sayo, and other people that were lured by Aria and her family, were imprisoned. Ieyasu called out to Tatsumi and told him how Aria and her family was responsible for his and the dead Sayo's fate. He watched as Tatsumi killed Aria and was happy at the sight as he thanked his friend for avenging his and Sayo's fate. He then succumbed to the last stages of Lubora disease after managing to stay alive through sheer willpower.
Equipment and Skills
Ieyasu was shown to wield an axe. He presumably possessed combat abilities on par with Tatsumi, as they and Sayo trained together since they were little.