Seventh Seal (The Hellion Trilogy Book 1)

The Intercontinental Supernatural Control (or I.S.C. for short) was created as a global organization whose purpose is to destroy all non-human beasts that threatened the human race and to help the human and supernatural worlds live in peace. The two worlds were meant to stay completely separate and, with any luck, ignorant of each other. To achieve this mission, the I.S.C. enlists the help of both humans and supernatural creatures to handle any problems that may arise.
Problems like David Johnson.
David is a unique case. He is the only known case of a half-breed demon to exist in the world. Born a human, and turned part demon in a tragic accident that killed his family, David is looking for his place in a world where neither human nor creature welcomes him.
As David starts to find comfort with Cathy, the first werewolf on record who can transform at will and daughter of his Commanding Officer, Hemah, the Fallen Angel of Death, begins her hunt for him.
David is seen as an abomination in the eyes of Heaven, and Hemah believes that he must be eliminated to secure her return to heaven in good graces. However, no angel has dared lay a finger on David because he is considered an agent of Hell. And if a demon or angel kills the other the war between Heaven and Hell begins, and earth will be their battlefield.