The great turmoil abounds in the human world when Corvus, the bogeyman enters and produces a deadly, dark mist and black rains to turn it into the world of Shadows. The living humans' shadows, which believe to be the human souls are turned into Shadows of Darkness by inhaling the mist, causing the victims to die and turn into stones. Alexis Briant, who is an asthmatic high school teacher also inhales the deadly mist and loses consciousness to his death. But fortunately, his life is spared when someone saves him before he completely dies from suffocation. When he regains his consciousness, he meets Rei - a mysterious masked man who claims to be the Reaper with no shadow and has his mission to defeat Corvus to reverse his cursed fate. With Alexis' help, they must journey to Corvus' castle in the new world of Shadows and this is how their thrilling adventure begins...