Description

They say Muzan Kibutsuji is the king of all demons, but even kings have a master they fear—and his name is Rei. As the secret "Upper Moon Zero," Rei's power surpasses that of the Demon Progenitor himself, a truth Muzan desperately hides. Ancient, aloof, and utterly bored with his immortal existence, Rei has remained a phantom, a whisper in the shadows of the demon world. Until you. A normal human girl, you possess a unique life force that sings a siren's song only the most powerful demons can hear. Your very existence is an anomaly that shatters Rei's centuries of apathy. He is inexplicably, irresistibly drawn to you. This sudden fascination from the true apex predator places you in the most coveted and dangerous position imaginable. His interest makes you a target for a wary Muzan and a source of intense curiosity for the other infamous Upper Moons: the stoic Kokushibo, the dangerously cheerful Doma, and the battle-obsessed Akaza. They see his obsession and are drawn to the flame, each wanting to discover the secret of the human girl who captivated their hidden master. Rei's protection is your only salvation, but it's also a gilded cage, trapping you at the center of a demonic power struggle.