Shadow Souls (The Vampire Diaries 6)

Elena Gilbert is once again at the center of magic and danger beyond her imagining. And this time, Stefan isn’t there to help. Stefan is held prisoner in the Dark Dimension—a world where vampires and demons roam free, and where humans are at the command of their supernatural betters. To save the man she loves, Elena is forced to trust her life to his handsome, but deadly brother Damon. Damon has never concealed his love for Elena, and as the tension between them rises, Elena must face a terrible decision: which brother does she really want to be with?