Kouji Kabuto pilots Mazinger Z and other mecha across various media. Originally an ordinary high school student, he lived with his younger brother Shiro and grandfather Juzo after his parents were presumed dead in a laboratory accident. His life transformed when Dr. Hell murdered Juzo; with his dying breath, Juzo revealed Mazinger Z and tasked Kouji with fighting Dr. Hell's forces. Kouji vowed to avenge his grandfather while protecting others from mechanical beasts and alien threats. Initially hot-blooded, reckless, and arrogant, Kouji often acted impulsively in battle, clashing with allies like Sayaka Yumi due to his dismissive attitude toward her combat abilities. He displayed a protective streak toward Shiro and gradually formed a complex friendship with Sayaka, marked by frequent arguments but mutual concern. His brashness extended to interactions with other characters, including a one-sided rivalry with Boss and initial friction with Duke Fleed. Despite these flaws, Kouji demonstrated loyalty and compassion toward friends and family, risking his life for them and showing willingness to self-sacrifice. Across his appearances, Kouji evolved from seeking revenge to embracing a broader sense of duty. In Great Mazinger, he reunited with his father Kenzo, previously thought dead, but lost him again battling the Mycenae Empire. This loss deepened his resolve to protect others, leading to alliances with characters like Tetsuya Tsurugi. In Grendizer, Kouji shifted to a supporting role, initially piloting the reconnaissance-focused TFO before designing and operating the combat-capable Double Spazer to aid Duke Fleed against the Vegan Empire. His relationship with Duke evolved from rivalry to mutual respect, though Kouji challenged Duke's methods when they conflicted with his ideals. In the film "Grendizer, Getter Robo G, Great Mazinger: Kessen! Daikaijuu," Kouji piloted Great Mazinger alongside Duke Fleed's Grendizer and Ryo Nagare's Getter Robo G against the Dragonsaurus, a giant sea beast threatening Tokyo. This collaboration highlighted his integration into team-based missions, contrasting his earlier solo tendencies. His participation aligns with his established role across media, frequently appearing alongside other super robots like Getter Robo in non-canonical battles. Kouji's technical skills grew significantly; starting as a motorcycle enthusiast, he mastered Mazinger Z's systems and later designed advanced aircraft like the Double Spazer. His combat style emphasized direct confrontation, often vocalizing attack names. Despite setbacks like injuries or temporary defeats, his perseverance remained consistent. In later stories, he transitioned from piloting to scientific work, reflecting his family's legacy, though he returned to action when new threats emerged.