Mosaic Moon (The Master Chronicles)

Emma Coolidge is accustomed to isolation. Born with the ability to read emotions, Emma reached adulthood without learning how to control her special gift, leading to a life of self-imposed seclusion. Until she meets Gideon Keel and Jesse Madding, a vampire fighting for good and his human lover. Both men befriend her and introduce her to people who can help her create a normal life for herself. Everything is great for Emma for the first time in her life--except for one small problem. She longs to be part of Jesse and Gideon's lives, and their darker games involving bondage and sadism, but believes her desire can be nothing but a private fantasy.

Gideon adores Jesse and wants nothing more than to give him everything he wants. When Gideon realizes Jesse wants Emma, as well, he decides to invite Emma into their games. But a disturbing new crime distracts Gideon from his goal. Jesse and Gideon are forced to investigate a string of grave desecrations that are somehow siphoning power from the most powerful mage in Chicago. They must unravel the mystery of who is stealing Black John's power, why, and how to reverse it before they can devote their time and energy to their mutual desire for a third in their bed.