When a boy watches the Devil King tear his father from the world, vengeance becomes his only purpose. Bound to a blade bathed in the blood of ancient devils, he joins a ruthless cousin and an unexpected ally—the Devil King’s own forsaken son. Together, they carve a path through the ranks of hellspawn, facing horrors that twist the line between man and monster. But as they draw closer to the throne of darkness, the weight of blood, betrayal, and sacrifice threatens to shatter more than just their bodies. Not all who begin the journey will live to see its end.
A boy named Mortis Theristis is pulled between two worlds. On Earth he’s a regular kid, wanting to skip school to train; in the Underworld he’s the last hope foretold by prophecy. Lucifer - who has already murdered the Theristis bloodline - destroys the family home and kills Ander and Machira while Mortis watches helplessly. With his final breath, Ander tells his son to find his cousing - one of the last remaining demon slayers - Gallord. Mortis, now burning with vengeance, vows to finish what his bloodline started: Lucifer’s complete annihilation.