Surrender to Darkness — E.J. King

Grace Hardwick has finally adjusted to life in the Darkness– a place where the sun never shines and supernatural creatures roam freely. She's even allowed herself to fall in love with one of those creatures, a centuries-old vampire who also happens to be Premier of the Darkness.But when the Darkness is attacked by a powerful group of Hunters, everything changes for Grace and William. Now, it's Grace's turn to protect him, even if that means she must sacrifice herself. This time around, the Guardianship isn't their only threat and time isn't on their side.