The protagonist, an aspiring yakuza who idolizes boss Tosa. After being shot alongside Tosa, he is resurrected as a metal-eating cyborg by scientist Genpaku Hiraga. He embarks on a revenge quest against the gang members who betrayed them, ultimately confronting Saratake and Fuku. His cyborg body grants him bulletproof strength but requires metal for energy and emotional control commands. He forms a bond with Yukari and avenges Tosa's death before being rebuilt at the film's conclusion.
Hagane maintains a professional and historical tie to the Nakame yakuza clan.
Despite initial friction, Junji eventually becomes a loyal companion and driver for Hagane.
Hagane and Yukari develop a romantic bond, though it is complicated by Hagane's cyborg nature and Tosa's lingering presence.
Hiraga is the scientist who surgically transforms the dying Hagane into a cyborg using Tosa's remains.
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