A member of the Yaminobu, Sumita is a large but relatively soft-spoken man who fights by way of a large battle-axe. After Nakajō is killed in the Binding Forest by the hitokiri Himura Battōsai, Sumita heads out with Yatsume Mumyōi as a second wave. Even with Battōsai's sense of hearing hindered by Nakajō's "binding" explosion, Sumita is no match. Shrugging off the ninja's vicious attacks, Himura cuts off Sumita's legs at the knees and leaves him to die. Differently in the IVA, he was run through the chest. Either way, Sumita catches his opponent's attention long enough to trigger the second binding explosion, sacrificing his life to damage Battōsai's vision with a large flash bomb.