Frost

The King of the human realm waged war on the Fae, taking the young Fae Prince back as his prisoner after slaughtering his family in cold blood. For two and a half decades, Prince Crispin has sat in the dungeons of his mortal enemies' castle. Rory is a young commander, desperate to prove herself to the King she serves under. But her blood has a secret that could ruin her life if the King finds out what she really is. She hides under the mortal King's nose as he continues to wipe the earth of all the Fae with unrelenting force. Her fate lies within a choice between duty and righteousness. A challenge. A ring. A spellbook. The fate of the Fae and the two Kingdom's rest in the hands of these three.