MARCUS (Le Beau Series Book 10) by V.A. Dold

Marcus Le beau found his one true mate, but there’s one huge problem. She’s there to kill him.
Cassidy Ryan’s last contract should be easy. So why is she hesitating? Was she given a bogus contract? Is that why her little brother is being held prisoner until she finishes the job?
If she fails to follow through, her brother will pay the price.