Empire of Flame and Thorns by Marion Blackwood

A fae rebel. A ruthless dragon commander.
And a deadly trial that will turn their lives upside down.

Trapped in the Seelie Court by a forest of thorns, Selena Hale lives at the mercy of the dragon shifters. Her only chance to gain her freedom is by entering the Atonement Trials: a deadly competition that pits fae magic users against each other. Only three people can win, and Selena intends to be one of them.
There is only one problem. Draven Ryat, the ruthless commander of the dragon shifter army, is determined to make her lose.
He symbolizes everything that she hates, and if he finds out that she is also a member of the secret fae rebellion, he will not only mess with her chances to win, he will kill her. But the more time she spends with him, the more she finds herself inexplicably drawn to him.
And nothing is more dangerous in a lethal trial than a distracted heart.
Especially one that beats for the enemy…