In 1999, the year Nostradamus famously predicted the end of the world, Japan finds itself in the grip of a massive occult boom. Amid this fervor, Hirotaka Asama, a weary and apathetic photographer who possesses the unwanted ability to see the supernatural, works for a third-rate occult magazine. His partner is the energetic and career-driven editor Shioi Inubousaki, who is constantly chasing a story but cannot perceive the spirits that plague her colleague. As Asama's psychic sensitivity draws increasingly terrifying and bizarre phenomena toward them, the duo investigates a series of horrific cases, from a cursed mirror that preys on children to rural towns haunted by dog-like spirits. The narrative is built around a tragic foregone conclusion established from the very first chapter. Twenty-four years later, in 2023, Inubousaki is dead. Her nephew arrives at the home of the now-aged Asama, desperately seeking the truth about his aunt's brutal and mysterious death. As Asama reluctantly recounts his forbidden memories of their time together, the story unfolds as a flashback within a framing device. He details their investigations into ancient evils suggested by Jomon-era ruins, possessed Buddhist monasteries, and the tragic end he witnessed. The mystery driving the narrative is the meaning of the title itself, Nikubami Honegishimi, a concept from the past that Asama is terrified to confront. Notable arcs include the case of the Purple Mirror, a malevolent entity that adopts lost children as its own before consuming their souls, and an investigation into an Inugami curse where a man created man-faced dogs by decapitating starved animals.