A retro-punk imperial capital, steeped in classical romance and overrun by malevolent spirits known as Magatsuhi, serves as the stage for a bizarre partnership. Taka'akira Akifusa is a rigid, duty-bound military policeman who despises the idle lifestyle of his childhood friend Chiaki Hanabishi, a playboy who lives on inherited wealth and spends his days chasing women. Taka'akira’s unit is investigating a string of gruesome murders dubbed the Ladykiller cases, where young men are found with their faces torn off and limbs severed. While warning Chiaki to be careful, Taka'akira is suddenly attacked by a Magatsuhi monster. He is rescued by a young sword-wielding priestess named Kikyo, who exorcises the spirit with a single blade. The next day, Taka'akira learns he has been transferred to Special Branch Zero, a secret unit dedicated to handling Magatsuhi and other supernatural threats. He is assigned as Kikyo’s partner, though he is troubled by a nagging sense that they have met before, long ago. Meanwhile, Chiaki’s carefree attitude and mysterious connections pull the trio into a tangled web of old bonds and hidden truths. As Taka'akira and Kikyo investigate boundary‑land incidents and confront powerful Magatsuhi, Kikyo’s concealed identity is eventually forced into the open, leading to a decisive confrontation that tests Taka'akira’s loyalty and forces him to make a crucial choice. The series spans two volumes, concluding with the revelation of Kikyo’s true nature and the resolution of the duo’s intertwined past.