Heizō's father is a minor character of Ginga Densetsu Weed: Orion.
Ginga Densetsu Weed: Orion
One day Hanashiro Shinkichi and his pack attack them. Heizō's father ordered to his mate, Heizō, Hiroko, and Taichi to flee and go back to their leader. In the end, he and his older sons, Yoshinao and Junpachi were killed by the enemy pack, trying to protect the family.