The Faceless Mage by Kenley Davidson

He’ll protect her with his last breath…
Until she becomes his next target.
Leisa’s ambitions used to be simple. Guard the princess. Hide her magic. Wait for her family to return.
But all of that changes when her king demands that she use her unique abilities to spy on the rival kingdom of Garimore.

Alone, far from home, and living a lie that grows more perilous by the day, Leisa’s task is complicated by her most dangerous enemy yet—the masked assassin known only as the Raven.
Everyone in the Five Thrones knows to fear him, but the Raven is not what Leisa expected. As silent as he is lethal, he provokes her curiosity as much as her fear, and hides secrets she’s determined to learn.

When her already precarious mission takes a deadly turn, Leisa must evade the Raven himself if she is to succeed. It’s never been done before, but Leisa is nothing if not stubborn. And if she doesn’t become the first to escape his blade, her entire kingdom will pay the price—in blood.