The Queen's Curse (The Soulfire Duology)

Ari has only known a life of servitude in Noctharn. As a mortal, seen as weak by the powers in her kingdom, she has endured sixteen long years of torment in the soulfire mines. She, like most in Lumin, despises eldarim, the elite members of society with the right to claim immortality from Althara, the highest power in the realm. Desperate to provide a better life for her mother, when the king calls for fighters, assassins, and hunters to search for his lost heir, Ari doesn't hesitate to join the quest. What she doesn't realize is that Lincoln Ashfield, the most skilled assassin in Noctharn, has joined it, too. But Ari doesn't give up easily. She would rather die trying than stay stagnant, and she will stop at nothing to find the lost heir and earn the life she deserves.