Blood of the sorceress - Maggie Shayne

Their Love was destiny.

Was a curse to be their undoing? As an ancient king's favourite harem slave, Lilia committed the worst possible crime: loving another man. When the king discovered her treason, her beloved Demetrius was sentenced to lose his soul and linger in eternal imprisonment, and Lilia was executed.

Lilia has been waiting for Demetrius to break free from his prison before she reincarnates, but without his soul he has become a demon. Somehow Lilia must convince him to reclaim his humanity - or both of them will be condemned to eternal damnation, their love lost forever.