Saving Hearts by Claire Cullen

Aiden has spent three years of his life as the live-in Omega of Vincent Hart, a wealthy Alpha with exacting standards and a cruel streak. Aiden wants to leave but it’s not just him he has to think about.
Enter Mac, the new security guard. Aiden avoids him at first, but the Alpha is kind in a way Vincent has never been, and there’s no denying the attraction between them. When Mac offers Aiden a way out, the Omega realizes there’s more going on than he can see.
For Mac, working for Hart is a step in the right direction, until he’s recruited by the shifter crimes unit to spy on his new employer. They suspect Hart is involved in the buying and selling of Omega and it is Mac’s job to help them prove it. He just wasn’t expecting Aiden, the Omega living in Hart’s house, in Hart’s bed. It doesn’t take long to figure out that Vincent has a hold over him, something keeping Aiden from running. Mac must find a way to get them both out safely, all the while keeping Hart in the dark about his and Aiden’s growing attraction. Simple, right?