One year ago, Akira Walker fell into a hole and found himself in a shadow world. The world is much like ours, with the same places and buildings, but the world is rife with magic and danger. After a brutal introduction to the world, Akira learns he can use Shadow, a powerful but unstable form of magic. While he explores this new world and the limits of his powers, someone in the Real World is killing people with Shadow.
At risk for exposure or attacks, and in seek of revenge, Akira uses his wit and guile to create a network of informers and comrades to hunt the serial killer. He continues to keep his secrets and live his normal life, but finds himself changing into someone cold-blooded and dark, filled with shadows. As he struggles to solve the mystery and come to terms with his new self, Light magicians and the police stand in his way. Akira becomes entangled in battles, using his wit, sword skills, and magic to protect himself, his identity, and his family. However, he is betrayed and arrested for the murders. As an escaped prisoner, Akira works against time to find out the devastating truth.
In the epic conclusion to the Devil's Deal series, Freya has one final chance to discover the full potential of her own power, and to use it to restore balance in the universe - once and for all. After the destruction caused by Roisin, Ferya and Torix come to terms with their losses and mistakes... And prepare for a final battle that will change everything.