Masaru Kodaka, who is nicknamed Kodama, is one of the fifteen middle-school students who unwillingly become pilots of the giant robot Zearth. He is the third child to pilot Zearth, taking control during the battle against the enemy mecha known as Cancer. Kodama is introduced as a relatively quiet boy who prefers to keep to himself, but his outward reserve masks a deeply warped moral sense shaped by his upbringing. His father runs a civilian contracting company and raised Kodama to believe that he and his family are chosen, superior beings, while everyone else is worthless. This belief leads Kodama to exhibit an arrogant and contemptuous attitude, and he takes open pleasure in cruelty, as seen when he burns a crab to death for fun and shoots at stray cats with a pellet gun. He even wears Kokopelli’s glasses to imitate the appearance of intelligence, further reflecting his desire to emulate his father.

Kodama’s primary motivation is his unwavering admiration for his father. Unlike his two gifted older brothers, who resent their father and have chosen different paths, Kodama looks up to him and accepts his worldview without question. This admiration extends into his role as a pilot: during his battle, he makes no effort to avoid civilian casualties and instead marvels at the destruction he causes, viewing it as a confirmation of his own superiority. However, his sense of wonder is abruptly shattered when a misstep causes Zearth to crash on top of his father’s car, killing the man instantly. For a brief moment, Kodama is stunned and horrified by what he has done, but he manages to compose himself and use his knowledge of construction—gained from his father’s business—to defeat Cancer. He dies unceremoniously moments after his victory.

Kodama’s key relationship is with his father, whose influence serves as the foundation of his personality and actions. His brothers, who stand in opposition to their father, highlight Kodama’s divergent path. Among the other pilots, Kodama is a solitary figure; he does not form close bonds with the group, and his callous behavior and high death toll (50,000 casualties during his battle) mark him as one of the most morally troubling characters. His development is minimal—his worldview is never reformed, and his death is abrupt and anticlimactic. The primary significance of his piloting arc is that his death finally reveals the truth to the other children: that piloting Zearth costs the pilot’s life. Kodama possesses no supernatural abilities; his only noteworthy skill is a practical understanding of construction, which he uses in his final moments to defeat his opponent. His entire character serves as a dark cautionary example of how parental indoctrination and a lack of empathy can lead to tragedy on a massive scale.