The Silent Prince by L Eveland

I will be free, even if it kills me.
As a prince of Ostovan, I had everything I wanted: the finest wine in my cup, scores of attractive knights to duel and bed, and an endless library of books. I never even saw my brother’s betrayal coming.
Captured and stripped of my voice by a magical collar, I’m sold as a slave to a warband of elves. I’ll stop at nothing to get both my freedom and my voice back, even if it means risking death at the hands of my captors.
And none of my elvish captors is more dangerous—or alluring—than Prince Ruith. Deceptively charming and deviously brutal in his methods, Ruith’s only goal seems to be torturing me daily for his own entertainment.
The more time I’m forced to spend with him, the more I find I crave his particular brand of cruelty. Despite his treatment, I come to see Ruith as my protector…and maybe something more. There’s definitely a spark between us, one that could turn into an all-consuming inferno if I’m not careful.
But he’ll only ever see me as a pawn in his power games, and I can only afford to treat him like my enemy, especially if I want to get this collar off and return to Ostovan to kill my brother.
I will have my vengeance, even if it kills us both.