The manga's story is an homage to Edogawa Rampo's fictional character Akechi Kogorou. The mystery centers around Mayumi Hanazaki, a middle-school girl who used to live with her aunt and uncle until a mysterious person mercilessly killed both. Now, thanks to an unusual incident, Mayumi relies upon the spirit of the legendary detective Kogorou Akechi to solve case.

(Source: Anime News Network)