Hayato Jin emerges as a young revolutionary leader exhibiting terrorist tendencies and unstable, psychopathic behavior, brutally punishing subordinates who question his authority. His background includes plotting political assassinations out of boredom prior to meeting Ryoma Nagare and Dr. Saotome. Witnessing the Dinosaur Empire's threat directly leads him to join the Saotome Institute as a Getter Robo pilot, where his exceptional agility and athleticism secure his role operating the ground-based Getter-2 formation. He possesses an athletic build, dark shoulder-length hair, and piercing eyes. His standard attire is a dark blue jumpsuit pilot suit paired with a white helmet featuring red decorations. Later iterations depict scars from mission injuries, notably in Getter Robo Go where he wears a black coat and sunglasses. By Getter Robo Arc, his aging body restricts his piloting capabilities. Personality-wise, he evolves from a violent nihilist into a cynical realist. Post-recruitment, he develops tactical pragmatism, willing to sacrifice irrecoverable victims while fiercely protecting comrades. He mourns Musashi Tomoe's death and refuses to let teammates sacrifice themselves without joining them. Over time, he cultivates scientific curiosity in Getter Rays, studying Dr. Saotome's notes and eventually designing new robots like Getter Robo Go, mirroring Saotome's methods including pushing pilots to their limits during recruitment. His leadership employs manipulation for strategic ends, particularly evident in Getter Robo Armageddon where he murders Saotome to prevent an Invader infection and frames Ryoma, believing these actions necessary for humanity's survival. Key relationships define his path. His bond with Ryoma shifts from rivalry to uneasy camaraderie, fracturing due to conflicting ideologies like Hayato's betrayal in Armageddon. He maintains complex ties with Dr. Saotome, initially as a protégé before becoming his successor in Getter Ray research. Family connections include his cousin Ryuji, whom he fights when Ryuji joins the Hyakki Empire, and his sister Asuka Jin, whose abduction by the Dinosaur Empire and later transformation into an Oni in Getter Robo G intensify his resolve against extraterrestrial threats. Across continuities, his role expands. In the original manga and Getter Robo G, he repels the Dinosaur Empire and Hyakki Empire, participating in space battles involving Uzahra and the Hyakki mothership's destruction. In Shin Getter Robo and Getter Robo Go, he transitions to mentor and researcher, overseeing new pilot teams against future threats like the Andromeda Stellaration. By Getter Robo Arc, as head of the Saotome Institute, he mentors Takuma Nagare (Ryoma's son) and brokers a truce with the Dinosaur Empire, recruiting Emperor Gore's hybrid son Sho Kamui as a pilot. His ultimate fates vary. In Armageddon, he sacrifices himself alongside Ryoma and Benkei Kuruma during a Shin Shine Spark attack against the Invaders, ascending to Getter Valhalla for eternal combat. In the main manga continuity, he survives into old age, guiding subsequent generations while grappling with Getter Rays' legacy and evolutionary implications.