In for a Pound (All In Series, Book Two) by Carol Lynne

Cas Vargas loves undercover work. Though he envies the relationship his best friend has recently found, he will never give up the career he lives for to have a man. Bed partners, like trouble and never-ending investigations, have always come easily for Cas. When a split-second decision blows his cover and lands him in hot water with his bosses at the FBI, Cas is thrust into a new assignment: guarding Joey Barbati, the nephew of renowned crime boss Tony Lo Russo.

Joey Barbati left the sins of his father and famous uncle behind when he took a job as a host at an RV part in Wyoming. Grizzly bears notwithstanding, Joey loves the safety the Big Horn Mountains provide. The last thing he needs is a babysitter in the form of a tall, strong Fed with dark hair and bedroom eyes.

When it becomes apparent that someone is watching Joey, Cas and Joey go on the run to figure out where threat is coming from—the mob or the law. As the threats around them heat up, so does the chemistry burning between them, and despite his best intentions, Cas finds himself caring too much for the man he thought was just a job.