Anzai started participating in dogfights at a young age. He is owner of Unryū and Benigumo.

Byakuren No Fang

He won his first victory over Yoshimura's tosa with his dog, Unryu.

After the official fight, Anzai meets Yoshimura when he's walking his dogs. Yoshimura's puppy Zero attacks Unryu, but Unryū is too strong for him and he's nearly killed. Unryū then fights Yoshimura's tosa and kills it. Anzai keeps training Unryū to make him bigger, stronger and more evil. He practises Unryū's moves on straydogs, which is the reason why Unryū ends up killing Zero's mother.

After a couple of years, Anzai meets Yoshimura again in a tournement. However, Yoshimura wins the round and beat Unryū with Zero's help. He starts to think Unryū has lost his spirit and trains up a new dog called Beni Gumo. However, Beni Gumo is defeated by Zero and now, Anzai goes back to Unryū and train him to become stronger and faster.

After becoming the champion, Anzai trains even harder. The following year they enter the championship once more and awaits the meeting with Zero. The final fight becomes long and hard. Unryū is close to winning the match, but in the end Zero is victorious. He can’t believe he has lost, not only the championship, but also several months of training with Unryū.