Royal Hacker by Linzi Baxter

Secrets aren’t meant to be kept… Patty and her twin, Jessica, seem like typical modern women, both successful and self-confident. When Patty suspects her brother-in-law is cheating on her sister, she uses her secret hacking skills to track him to a BSDM club. After Patty confronts her brother-in-law at the club, the owner, Sam, seduces her. Several months later, Patty’s life is turned upside down when someone dangerous begins stalking her.

But there’s an even bigger secret—Patty and her sister are the daughters of the King of Shialia, and Patty is next in line for the throne. Fortunately, Sam is there to protect her, body and soul. And he’s going to have to work overtime, because everyone around him has their sights set on Patty. She’s worth a lot of money, but Sam is the only one who knows she’s priceless. And just when everything seems to work out, fate has a way of turning the tables.