Blood of Dragons by Penelope Barsetti

The Death King betrayed me—so I did the same to him.
My time in Talon’s captivity has complicated my feelings. He’s more than a monster that conquered innocent people for his own means. He carries a lethal wound no one can see, a justification for his cruelty. But I have wounds too—wounds that he caused. My entire miserable existence is because of him—a cruelty he will never understand even though he should understand it most.
Inferno, the powerful red dragon that’s fused his soul with mine, and I have agreed that the Death King must be exiled. We travel north to Riviana Star, the forest home of the elves and my father’s brother, Ezra. I assumed I would be welcomed with open arms—but I’m treated with only suspicion by Queen Eldinar. She grants me asylum in her forest because I’ve agreed to be their ally against the Death King— but begrudgingly.
Even when I’m in the presence of the elves, I drown in solitude. I’m the only one of my kind besides my uncle, but his reception of me isn’t warm like I hoped. Commander Luxe takes an interest in me, but my heart still yearns for a man it should hate. And that’s when he appears—The Death King—in Riviana Star.
But not in the flesh.
The Death King is far more powerful than I ever imagined—and I’ve made him my greatest enemy.