Just after the publication of her latest book, popular writer Kaoru Iwai suddenly dies a mysterious death. The police conclude that Iwai's death was a suicide, but the protagonist, mystery writer Yu Kizaki, discovers the hazy reflection of an unknown man in a photograph taken at a book release party held just before her death and, suspecting that he murdered her, begins searching for the man's identity. This is the story of a writer whose life is eroded by the shadow of an unknown man in a photograph.