Kushiel's Avatar (Phedre's Trilogy #3)

Kushiel's Avatar (Phèdre's Trilogy #3)
The land of Terre d'Ange is a place of unsurpassed beauty and grace. It's inhabited by the race that rose from the seed of angels, and they live by one simple rule: Love as thou wilt.
Phèdre nó Delaunay was sold into indentured servitude as a child. Her bond was purchased by a nobleman who recognized that she was pricked by Kushiel's dart, chosen to forever experience pain and pleasure as one. Phèdre's path has been strange and dangerous. She has lain with princes and pirate kings, battled a wicked temptress, and saved two nations. Through it all, the devoted swordsman Joscelin has been at her side, following the central precept of the angel Cassiel: Protect and serve.
But Phèdre's plans will put his pledge to the test, for she has never forgotten her childhood friend Hyacinthe. She has spent ten long years searching for the key to free him from his eternal indenture to the Master of Straights, a bargain with the gods to save Phèdre and a nation. The search will take Phèdre and Joscelin across the world and down a fabled river to a forgotten land. . . and to a power so intense and mysterious, none dare speak its name.