The former yakuza boss and Kensuke Hagane's idol. After a failed assassination attempt on rival Masashirenbo, he is imprisoned for seven years. Upon release, he is betrayed and shot alongside Hagane. His heart and distinctive back tattoo are surgically transplanted into the cyborg Hagane. Though deceased, his memories and physical parts play a central role in Hagane's transformation and motivations.
Tosa and Yukari share a past romantic relationship that ends when he prioritizes his yakuza duties over her.
Hagane deeply reveres Tosa, maintaining a loyal connection to him even during his imprisonment.
Explore the full interactive character relationship map of Full Metal Yakuza