Krovs: Into Darkness by M. Lee Woe

Sure, Tristan’s attractive and has had several lovers, but he refuses to be labeled a playboy. After all, it’s not his fault that he’s always been surrounded by a group of female friends all vying for his love and attention. Imagine his surprise when he learns that none of his lovers have ever been human. That he—along with others—were trained since adolescence to please the females of a superhuman race called Krovs!
Regardless of his friend’s attempts to keep him away from human lovers, Tristan accidentally falls for a virtuous woman named Serene, but will his training prove too much for her?
When Tristan’s super powerful ex-girlfriend finds out about their union, his world is turned upside down. Everything he thought he knew about his friends was a lie!