He is wise, caring and an excellent fighter. He blames himself for Masamune's doing because he thinks he didn't raised him right.
Ginga Denesetsu Weed: Orion
One day, he finds Masamune wounded in the mountains and decides to adopt him as his own son. In addition, he trains Masamune relentlessly to become a strong fighter. Although Masamune tries his best to satisfy his father, he turns his attention to his young son, Yamabiko, who has just been born, and already decides that he shall be the heir of leading the Kurohabaki Clan.
This causes Masamune to turn vengeful and bitter. To prevent any incident, Terumune sends Yamabiko to Shikoku along with his guardian Kojūrō. Afterwards, Masamune fights Terumune and eventually defeats him. He is then banished from the pack and Masamune becomes the new leader of the Kurohabaki Clan. His pack members, along with Yamabiko and Kojūrō , never heard from him again.
When volcanic eruptions happened in Ohu Terumune comes across Gin's pack and helps guide them through the flames but he sees the pack pass out because of the smoke and leaves to find help. He leads Kurohabaki Jinemon to where the dogs are and carries them to safety
One night, while traveling in the cold mountains of Ohu, he meets Rigel, Weed's son, who got lost in the storm while searching for his brother, Orion. Terumune decides to look after the black furred Akita/Kishu-mix puppy and continues his journey.
On the way, he meets Izou, Kisaragi's eldest son, along with his brothers and they ask him the direction to the Kurohabaki Clan base. Terumune is disturbed about this proposal, but tells them anyway to avoid conflict.
As they continue, he picks up a strange scent in the snow and starts to dig. He and Rigel are shocked to find a pile of dead bodies and all of them are huskies. As he looks around, he noticed Masashige's sent and finds Kisaragi's body in the pile finding out that the other bodies were his deceased sons. He also finds out that Rigel is the son of the legendary leader of Ohu, Weed, as the puppy mentions his father, crying in grief.
He decides to train Rigel to become a strong young male, just like his elder brothers Orion and Sirius, who are in Shikoku in the meantime. Rigel's training wasn't easy, but Rigel started to get used to it and was now capable to hunt independently. One day, Terumune felt ill and had to cancel Rigel's training.
When an assassin called Shinnosuke appears, Rigel kills him with a ninja technique taught to him by Terumune. Even though, he was an assassin Rigel and Terumune buries him and Terumune leads him to the shed wear they are being held, the black akita is able to dig his way through the snow. Terumune opens up a small hole allowing him to go in but he couldn't brake the cage to free them so they left.
While Rigel fetched him something to eat, Weed visited him, eventually telling him where the Ohu survivors are being held. When Rigel returned, the Kai-ken told the puppy that his father was alive and that they must leave at once to find his family. However, they were surrounded by Masamune's henchmen, who were given orders to assassinate their banished leader.
Knowing that Rigel's life was in danger, he ordered him to escape to find his family while he held them off and Rigel obeyed and left. Terumune was a skilled fighter, but was too sick to fight, completely outnumbered and the evil dogs easily brought him down.
Terumune was just about to face death until Rigel returned to save him. Unfortunately, Terumune had his throat cut by Kurokirimaru and his brothers and he died before Rigel could save him.