Full Metal Yakuza

Tosa abandons Yukari to pursue the rival Masashirenbo, failing to complete the job. His actions lead to his seven-year prison sentence. This marks the end of his immediate relationship with Yukari and sets up Hagane's future in the underworld.

Upon his release, Hagane is welcomed by the loyal Kensuke who idolizes him. The two are lured to a location where rival gangs shoot them, intending to crown Saratake as boss. Their bodies end up in the hands of Genpaku Hiraga, the scientist who will start Hagane's cyborg transformation.

Genpaku Hiraga revives Kensuke by replacing much of his body with cybernetic parts and giving him a heart, a full-back koi tattoo, and enhanced abilities. He nicknames the cybernetic fighter 'Lead' and monitors Hagane's combat capabilities remotely from a laptop. Kensuke becomes nearly invincible and dons the new identity to seek revenge.

Hagane, now a cyborg, can only consume metal as energy, fueling his strength for vengeance. He leaves Hiraga's care to hunt down those who killed Tosa. Hiraga continues to oversee his performance, gathering data from his battles.

At a driving range, Hagane corners the duplicitous gang members who lured him and his mentor. He forces underboss Maeda to name the killer, who turns out to be Kamane Haga. The revelation sets Hagane on a direct path to Kamane.

Junji begins sleeping with Hagane's old girlfriend Naomi, complicating loyalties within the yakuza world. Hagane warns Junji not to hurt her, underscoring the fragile lines between personal and criminal conflicts.

Hagane fights his way into Chief Fuku's office and kills the shooters. Kamane reveals that Maeda and Saratake were behind the ambush. Hagane returns to Nakame's headquarters, where Saratake kills Maeda and tries to pin the blame on him, prompting Taka to intervene and prevent Hagane from killing Saratake.

Hagane begins a relationship with Yukari and must use a special command to control his emotions and avoid a short circuit. Yukari ultimately leaves him, unable to forget Tosa while seeing Hagane's koi tattoo. She later attacks Saratake posing as a golf-course caddie, only to be stopped by Taka.

Junji provides Hagane with a photo of Yukari naked and bound, provoking Hagane's fury. Later, Yukari is raped by Taka; she bites off her tongue to commit suicide, sealing a tragic turn in Hagane's quest.

Saratake calls Hagane to kill Masashirenbo in exchange for Yukari's safety. Hagane kills Masashirenbo and experiences Tosa's memories of Yukari's disappointment in him.

Taka orders explosives to demolish Hagane's beach shanty; Hagane senses the impending attack and escapes with Jinji, leaving behind only a detached cyborg eye to mislead his attackers. The enemies believe Hagane is dead.

Saratake and Fuku seek the doctor who built Hagane to gain more robot soldiers for their war against Nishida. Jinji, loyal to Hagane, joins him and helps locate Yukari.

Jinji arrives with the doctor to rebuild Hagane, restarting his quest for vengeance. The cycle ends with Hagane continuing to walk the path of a cyborg warrior, as new allies and enemies converge.