Hard Risk by Sidney Bristol

Harper Wright enjoys working off-the-books for the government, and his next assignment is a treat. All he has to do is get close to a socialite so he can get the scoop on her rotten as sin family. But this socialite isn’t what he was expecting. Instead of being wrapped up in fashion and trends, she’s far more concerned with cancer research and fighting for rights. She’s beautiful, funny, kisses like sin, smarter than him, and one last thing? She’s using him.
Robin Suleiman knows her uncle killed her mother fifteen years ago, and now Robin is going to prove it. There’s just one problem. In her family, being female is practically a crime. So in order to get close to her uncle, she needs a man. When the universe provides, Robin is listening. She might be rusty when it comes to the opposite sex, but Harper is diligent about reminding her of all the reasons why men and women are so good together. So good that she begins to wonder if the mystery is worth uncovering?
The choice isn’t up to her when Robin’s uncle catches her snooping around. It’s the wake-up call Harper needed to remember that falling for Robin wasn’t the job. Now he has to keep her and his secret safe or risk losing it all.

Author recommendation: Due to spoilers, this series is enjoyed best when read in order. There are fewer spoilers in this book than others.