After a life of abuse ends in suicide, Kazuki is reborn in a magical world with god-like power and a hollow heart. He becomes the "Hollow Demon," a merciless force of destruction, until he meets Elara, a Saintess who tends a sunlit glade in a corrupt forest. Unafraid of his power, she sees only his wounded soul. Her stubborn kindness forces him into a truce, challenging his nihilism with stew, flower crowns, and rules. As Kazuki tentatively explores a life beyond destruction, external forces—a holy kingdom, greedy mercenaries, and a rising corruption—converge on their fragile peace. He must now choose: retreat into familiar emptiness, or use his infinite power to protect the first light he cannot extinguish.