Godou Kusanagi, a seemingly ordinary Japanese high schooler and former baseball prodigy, finds his quiet life upended when he inadvertently slays Verethragna, the Persian God of Victory, during a routine errand in Sardinia. By stealing the deity's divine authority, Godou becomes a "Campione"—a supreme god-slayer and one of the most powerful beings on Earth. This title thrusts him into a clandestine world of magic, mythological crises, and ruthless rivals, stripping away his anonymity and replacing it with the heavy burden of maintaining
supernatural balance.Almost immediately, Godou is approached by Erica Blandelli, a proud, sharp-witted "Great Knight" belonging to the Italian magic association, Copper Black Cross. Erica recognizes his newfound godlike status and quickly co-opts him into her chaotic orbit. As a Campione, Godou’s primary duty is not worshiping gods, but rather fighting rebellious, wayward deities who manifest in the mortal realm. These divine beings bring catastrophic calamities—such as relentless storms, plagues, and mythological beasts—in their wake.Alongside Erica, Godou’s harem-like entourage rapidly expands to include Lilyana Kranjčević, a talented knight and rival to Erica; Mariya Yuri, a sweet Japanese shrine maiden capable of spirit vision and spiritual reinforcement; and Liliana's half-sister, Ena Seishuuin, a fierce sword-fighter wielding a legendary blade. Each heroine is driven by a mix of political duty, mystical fascination, and genuine romantic affection for the reluctant teenager, often pushing him into embarrassing domestic scenarios while aiding him in high-stakes combat.The narrative escalates as Godou faces a series of increasingly formidable adversaries. He battles the brutal Marquis Voban, an ancient and tyrannical Romanian Campione who views humanity with utter disdain. He also confronts autonomous gods like Persephone and Melqart, whose divine clashes threaten to tear the world apart. Because Godou’s stolen authority requires him to understand the myths of the gods he fights, he must often outsmart brilliant masterminds like the scheming witch Lucretia Zola and unearth ancient lore under extreme pressure.Despite his immense power, Godou resents the violence and wishes for a peaceful life, yet his deep sense of
responsibility compels him to protect innocent lives. Through intense magical battles, strategic wit, and the collaborative strength of his fiercely loyal companions, Godou masters his divine powers. He successfully repels rogue deities, outmaneuvers rival god-slayers, and ultimately embraces his inescapable destiny as the ultimate guardian between the human world and the wrath of the heavens.