Takamaru was an Iga ganin.
His master trained him and his fellow ganins Akame and Kikumaru to wield swords and fight humans in war. His master was killed by Nobunaga Oda's men and Kōga ganin who had joined them. He and Kikumaru ran with the secret technique scrolls of Itō while Akame stayed to delay the enemies. He eventually stayed with Akame, Kikumaru and master's son Kotarō Itō. The Itō family carried on existing.