In a world ravaged by a mysterious virus that kills everyone over the age of thirteen, humanity is enslaved by vampires who emerge from the shadows to claim the survivors as livestock. Yuichiro Hyakuya, a headstrong orphan, escapes a brutal vampire facility after his
surrogate family is slaughtered by the noble vampire Ferid Bathory. Witnessing the gruesome death of his beloved friend Mikaela, Yuichiro is consumed by a burning desire for vengeance. He is rescued by the Moon Demon Company, an elite unit of the Japanese Imperial Demon Army tasked with exterminating the vampire menace using cursed demon weapons.As Yuichiro trains to master his own cursed blade, he discovers a harrowing truth: Mikaela has been transformed into a vampire against his will. This revelation shatters Yuichiro’s worldview, forcing him to navigate the gray morality of a conflict where both sides are driven by desperation and hidden agendas. The Imperial Demon Army is not the altruistic savior Yuichiro imagined; it is a corrupt organization experimenting with forbidden rituals to achieve god-like power. Meanwhile, Mikaela struggles with his newfound bloodlust, clinging to his lingering humanity solely to rescue Yuichiro from the military’s manipulative grasp.The narrative intensifies as the battlefield expands beyond simple skirmishes. The "Seraph of the End," a catastrophic project involving human experimentation, threatens to trigger another apocalypse. Yuichiro finds himself caught between his loyalty to his human comrades—who have become his new chosen family—and his undying bond with Mikaela. As the lines between human and monster blur, Yuichiro begins to unleash the terrifying, angelic power lurking within him, a force that could either save humanity or hasten its final destruction. The series culminates in a high-stakes confrontation where internal betrayals and ancient prophecies collide. Both boys must confront the reality that the world they seek to reclaim is already fractured beyond repair. Their journey is a visceral exploration of trauma,
the corruption of power, and the lengths to which one will go to protect the person who anchors their soul. In this dark, supernatural landscape, survival is not merely about staying alive, but about retaining one’s humanity in the face of inevitable, systematic annihilation.