Bound to the Bear by Rebecca Thomas

A fake relationship with consequences…

Werebear Stefan Vane has a job to do—protect his witness. He devises a plan to keep the stubborn she-bear at his family’s remote wilderness therapy camp. Her identity must stay secret. They agree to pretend they’re a couple. But her smart mouth and sexy curves are distracting. He’ll do whatever it takes to make sure she’s safe, only he never expects the lines between what’s fake and what’s real to become so blurred.

Tess Trevino is the only witness in a botched robbery attempt. The perpetrator is arrested, but her life is threatened. When witness protection sends an extremely hot detective to protect her, she can’t say no. Her stomach does twirly-twisty things when he’s near and since her bear has been in hibernation so long, she can’t resist him.