Crown of Midnight (Throne of Glass 2)

Eighteen-year-old Celaena Sardothien is bold, daring and beautiful – the perfect seductress and the greatest assassin her world has ever known. But though she won the King's contest and became his champion, Celaena has been granted neither her liberty nor the freedom to follow her heart. Celaena faces a choice that is tearing her to pieces: kill in cold blood for a man she hates, or risk sentencing those she loves to death. Celaena must decide what she will fight for: survival, love or the future of a kingdom. Because an assassin cannot have it all ... And trying to may just destroy her.