A young editor named Ozawa vanishes while investigating a series of paranormal phenomena for a failing occult magazine. His friend, a writer who uses the pen name Sesuji, compiles his research into a book, hoping that making the information public will lead to clues about his whereabouts. The investigation centers on a specific location in the Kinki Region, also known as the Kansai area, encompassing major cities like Kyoto, Osaka, and Nara. The truth Ozawa uncovered involves a convergence of disturbing events in this area, particularly in a rural, depopulated zone where multiple prefectures meet.

The narrative is not a traditional novel but a fictional "found footage" collage of documents. The book is presented as a case file assembled by Sesuji, containing primary sources such as archived magazine articles, interview transcripts, internet forum posts, reader-submitted stories, and letters. The main characters are defined by their roles in this investigation. Ozawa is the enthusiastic but inexperienced editor whose disappearance drives the plot. Sesuji is the compiler and narrator, acting as a detective figure who attempts to solve the mystery from the clues left behind. Other recurring entities are the phenomena themselves, including a tall white figure called Mashiro-san that appears in the woods, a woman in a red coat, a ruined house, an apartment building known for suicides, and unsettling children’s games.

The book is structured as an escalating series of interconnected mysteries. Early segments present seemingly isolated urban legends and ghost stories. As the reader progresses through the documents, connections begin to emerge between disparate incidents across different decades. A key narrative arc involves the discovery of a forgotten or abandoned shrine in the mountains. Local folklore suggests that a deity residing there, neglected and forgotten by a shrinking community, has begun to malevolently influence the living as a way to ensure it is not erased from memory entirely. This theme of belief as a powerful force—and the horror of things that persist after being abandoned—is central to the plot. The investigation ultimately leads to a final, unsettling hypothesis about the nature of the curse, presented as a flawed and possibly incomplete solution that the reader must piece together themselves. A film adaptation directed by Koji Shiraishi, known for his work in the Japanese found footage horror genre, has been released.