The Outsider (Harlequin Temptation, No. 385) (Rebels & Rogues)

Cameron Divine--The roguish research scientist came from light-years away on a mission. A flesh-and-blood woman changed everything.
Summer Van Vorn--A simple folk healer. Sexy, vulnerable, she'd been waiting all her life for the right man to come along.
Could that man be Cameron? Strangely, he was so much in sync with Summer... almost able to read her mind. And in bed, he was the perfect lover, anticipating every one of her desires. But Cameron could also be as unfathomable as the sea. There was something not quite human about him.