Ichiro Zinjuro was a bushi and sensei of the Heart of the Mountain Dojo. He was a scarred and seasoned veteran, twin brother of Ichiro Jinzaburo, chief advisor to the Ichiro Daimyo. Zinjuro was a harsh disciplinarian, who rewarded those who succeeded under his tutelage. Many regarded him as the spiritual successor to the legendary Ichiro Tashimi, the only sensei of the Ichiro Bushi style to survive the rampage of Hideo no Oni decades ago. Zinjuro took Tashimi's place after the latter's death.