Flamecaster / Cinda Williams Chima.

Enhanced descriptions from Syndetics:

Set in the world of the New York Times bestselling Seven Realms series, a generation later, this is a breathtaking story of dark magic, chilling threats, and two unforgettable characters walking a knife-sharp line between life and death. This dazzling beginning to a new series is indispensable for fans of Cinda Williams Chima and a perfect starting point for readers who are new to her work.

Adrian sul'Han, known as Ash, is a trained healer with a powerful gift of magic--and a thirst for revenge. Ash is forced into hiding after a series of murders throws the queendom into chaos. Now he's closer than ever to killing the man responsible, the cruel king of Arden. With time running out, Ash faces an excruciating choice: Can he use his powers not to save a life but to take it



Abandoned at birth, Jenna Bandelow was told that the magemark on the back of her neck would make her a target. But when the King's Guard launches a relentless search for a girl with a mark like hers, Jenna assumes that it has more to do with her role as a saboteur than any birth-based curse. Though Jenna doesn't know why she's being hunted, she knows that she can't get caught.



Eventually, Ash's and Jenna's paths will collide in Arden. Thrown together by chance and joined by their hatred of the ruthless king, they will come to rescue each other in ways they cannot yet imagine.