Saburo Tenma emerges as a young student in Hope Town, initially appearing somewhat overweight yet displaying early determination. He harbors protective feelings toward his teacher Keiko, attempting to defend her during Hell's Wind's attack with a makeshift bow—an act revealing courage despite limited physical prowess.

After the assault, Saburo witnesses Violence Jack's brutal confrontation with Hell's Wind. Jack sustains massive gunfire injuries, his blood splattering onto Saburo, and commands the boy not to look away from the violence—an event suggested to influence Saburo's later transformation. Saburo participates in transporting Jack's incapacitated body back to Hope Town. When townspeople resist fighting to rescue the kidnapped Keiko, Saburo confronts them with a passionate speech advocating resistance, indirectly motivating Jack to intervene.

In later manga narratives beyond the Hell's Wind events, Saburo undergoes significant physical development, becoming heavily muscular through strenuous wasteland activities like lifting rocks. He evolves into a capable fighter, eliminating threats to Keiko, including Slum King forces. During a confrontation where both are severely injured by gunfire, Violence Jack's Golden Bird entity fuses with Saburo, enabling him to defeat attackers, though Keiko perishes.

Saburo establishes the Tenma Army, capturing strategic locations like Black Drake Fort to form his controlled territory, the Land of Tenma. This positions him as a significant power against the Slum King alongside figures like Ryu Takuma. His journey concludes as a leader commanding his faction within the fractured post-apocalyptic landscape.