Tatsuo Nagumo, a shy and lecherous high school student, is fated to become the human vessel for the Chōjin—a divine entity tasked with uniting the human, demon, and man-beast realms through cataclysmic destruction. His dormant bloodline awakens apocalyptic prophecies, intertwining his life with supernatural forces. As the Chōjin’s power consumes him, he mutates into a demonic harbinger of annihilation, razing the world to create a new era ruled by his messianic offspring. Though initially a passive figure swept into chaos, Tatsuo’s choices ripple across realities. His bond with Akemi Itō, his girlfriend and the mother of his child, anchors fleeting humanity amid his descent into cosmic violence. The manga traces his tortured acceptance of this destructive role, while anime adaptations expand his legacy through familial ties. A fateful blood transfusion to save his cousin, Takeaki Kiryū, after a near-fatal plane crash inadvertently transfers the Chōjin’s power, corrupting Takeaki into the Kyō-Ō—an ancient evil rivaling Tatsuo’s own divinity. This act ignites a chain of events pitting Münchhausen II’s schemes against allies like Amano Jyaku and Megumi Amano, struggling to avert global collapse. Tatsuo’s arc oscillates between vulnerability and apocalyptic inevitability, his human relationships clashing with his function as a divine catalyst. The manga delves into his internal conflict and tragic embrace of destiny, while the anime underscores how his compassion for family spirals into unintended catastrophe. Across both narratives, his transformation embodies cyclical cosmic forces, merging intimate tragedy with mythic scale. Bonds with Akemi and Takeaki highlight the tension between personal agency and preordained roles, framing his journey as a collision of moral ambiguity and inexorable fate.