Unclaimed Mate by D.M. Mortier

Luka Petrov refused to let the brutal legacy of his Slavic vampire father and the unsavory legacy of his human mother define him. As Dhampirs, he and his brothers had vampiric powers and wealth that ensured that they were feared and revered in both the immortal and human worlds. Fate gave him a mate he neither wanted nor needed. His fated mate was supposed to further his Slavic lineage, which was on the brink of extinction, but Luka wasn’t interested in continuing that lineage. Their legacy was steeped in blood and violence, a lethal heritage that didn’t deserve to be preserved, at least that is the reason Luka had always given. He refused to admit to the real reason, not even to himself.
Unfortunately, there were many in the immortal world that wanted to see the end of the Petrov line, the existing line and were willing to violently ensure their demise.
Unwilling to claim his mate, and equally determined to protect and shield her from his enemies, Luka would destroy anyone who meant her harm. There was nothing he wouldn’t do to protect her.
Luna Cambridge didn’t understand the immortal world she’d been suddenly thrust into. Being told that the man she had only seen in her dreams was her fated mate had initially made her heartbeat accelerate with the possibilities, and then she met his mistresses. No power on heaven or earth would compel her to give in to the fated mate allure with a man who had so little respect for women, and certainly had no concept of monogamy. Fate made a mistake, and she wasn’t about to be lured into a path that is destined to fail spectacularly.