Heir of fire. Sarah J. Maas. 2014.

Consumed by guilt and rage, Celaena can’t bring herself to spill blood for the King of Adarlan. She must fight back....

The Immortal Queen will help her destroy the king - for a price. But as Celaena battles with her darkest memories and her heart breaks for a love that could never last, can she fulfil the bargain and head the almighty court of Terrasen? And who will stand with her?