One Cut Deeper - Burkhart, Joely Sue

Her needs are dark. His are dangerous.
Charlie MacNiall has been bringing his beautiful king shepherd to the vet clinic where Ranay Killian works for the better part of a year. She doesn't realize he's been slowly wooing her. She certainly has no idea that he picked her deliberately-that she is to become his. A broken heart and a desperate desire to be dominated make her the perfect victim.
His perfect victim.
Charlie fixes Ranay, testing her emotional limits while pushing her sexual boundaries past anything she'd imagined possible. Pain is their shared pleasure ... until Charlie disappears and Ranay is all but destroyed.
The FBI says the man she loves is a serial killer. Ranay can't deny there's a darkness in Charlie, a monstrous hunger that drives him to the brink. She even believes he could kill. But Charlie's hunger is what bonds them-it's the foundation of their love. Would he actually kill her ?