Alien Incognito by Cara Bristol

He betrayed her once, but he’s her only hope.

Being saved from a slave ship and given life-saving medical attention by a tall, muscular furry alien with large curling horns is enough for Giselle Cartier to think she’s found a hero.
Having him deliver her back into the clutches of the same traffickers shatters her trust and the belief that anything she’d felt was real.
But just as she’s rescued by the League of Planets and is about to be repatriated to New Terra, Joule reappears with the devastating news that Giselle’s sister has been taken.
What’s even more shocking is his promise to find her. He’s already betrayed her once; what’s to stop him from doing it again? How can she trust anything he says?
Regardless of the risks, she has to go with him. He’s her only hope for finding and saving her sister. This time, she won’t let her guard down. She also won’t make the mistake of falling in love with him again.
Long ago, Joule hardened his heart to the cruelty, misery, and death he’d witnessed in the alien species trafficking trade. As an agent with the League of Planets working deep undercover to combat the trafficking of sentient beings in the galaxy, he can’t afford empathy. To benefit the greater good, he’s often forced to make difficult, even reprehensible decisions.
But something about the vulnerable, critically ill Giselle Cartier pierces through the protective wall surrounding his heart. Choosing to save her life is startlingly easy—too easy. He should have known better than to let himself get attached.
Because circumstances force his hand, leaving him no choice but to take her back to the slavers. He couldn’t risk blowing his cover for a single human woman—even if he had fallen in love with her.
Now he’s involved all over again. When he learns Giselle’s sister has also been abducted, he can’t hold back from offering his assistance. Unable to reveal his real role, he must continue to let her believe he’s a trafficker—one who’s already betrayed her.
Giselle will never trust him again…which is smart.
Because she still can’t.