Darkbirch Academy 2: Embers and Secrets by Krista Graves

She was stolen by a dragon prince. Now she has to survive him. Esme Salem wakes beneath the earth in a palace of obsidian and flame: the heart of the hidden dragon realm of Draethys. Her captor, Lord Daynthazar, the firstborn prince, claims their blood has been irreversibly bound. By ancient dragon law, that makes her part of his hoard. Trapped in a kingdom built on fire and fear, Esme must decide fast whether Dayn is her captor, her only chance to survive—or both. Because in Draethys, dragons need little excuse to kill darkbloods—and something ancient beneath the molten rock is beginning to stir. Esme wants only one thing: escape. But the bond between her and Dayn is tightening, tensions are rising, and the line between hatred and heat is wearing dangerously thin. Because in Draethys, even enemies burn. Meanwhile in Darkbirch, Brynn must deal with another... situation. Read more