Making Waves by Michelle M. Pillow

When Demon, a merman tasked with patrolling the ocean for humans in distress, comes across a woman anchored to the bottom of the sea, he’s sure his dreams have come true. After all, she’s stunning, single, and makes his body burn with need. She’s also impetuous, being hunted by his enemies, and seriously conflicted on whether or not he’s a good guy. It’s his duty to not only protect her, but to win her heart–because this lonely merman is sure she’s the one for him. Now he just has to convince her of as much.