Servant of the Empire by Raymond E. Feist

Through the eyes of her Midkemian slave Kevin of Zün, she begins to see the flaws, contradictions, limitations and potential of the Tsuranuanni Empire - and finds a love like she has never known. Though challenging the norms of Tsurani society had served her well, Mara is still a product of her culture and does not question many of her beliefs and conventions. He enlists into this cause his cousin Tasaio, the cruel military genius who had managed to send Mara's father and brother to their deaths without breaking any laws or losing honor. Lord Desio of the Minwanabi, son of the defeated Lord Jingu, swears an unbreakable blood oath to the Red God of Death that he will destroy the Acoma or end his own bloodline. Having risen in wealth, power and social standing but still threatened by powerful enemies, Lady Mara of the Acoma is in as much danger as ever after her triumphs in Daughter of the Empire. After buying a group of Midkemian prisoners-of-war, she finds one of them - Kevin of Zün - to be a great asset in her ongoing struggle for survival and power. In the world of Kelewan, Mara of the Acoma has now become an expert player in the Game of the Council through bloody political maneuvering. When she finds a nobleman ( Kevin of Zün) among a band of slaves from Midkemia, she soon involves him too in her political struggles. Mara of the Arcoma, Ruling Lady of her house, has established herself as a force within the Empire and a deft player of the Game of the Council, the politics of the empire.

Servant of the Empire by Raymond E. Feist