This is the third book in the series “Blood of Kings” by Jill Williamson. Fabulous reading! It is very hard to put down! There is a part in this book #3 that I would have not written quite so explicitly. So that is why I recommend this book for 16 and up.
From the Publisher:
Darkness Trembles Achan steps into his role as Crown Prince and prepares for war. But war against whom? Could Esek still be alive? Has Lord Nathak taken Esek’s place? Or is the mysterious Hadad the true enemy Achan must confront? Vrell has her own agenda of serving Prince Oren as a healer, but when she is stormed and lost to the Veil, Achan does all he can to bring her back. His conversations with her are strange, though, as if she has no memory of who he is. In a land consumed by Darkness, the fate of Er’Rets hangs in the balance as Achan endeavors to take the throne and end the reign of Darkness.