Heart of the Dragon by Gena Showalter
Genre: Paranormal Romance
Searching for her missing brother, Grace Carlyle never dreamed she would discover a secret world populated by mythological monsters - or find herself facing a sword-wielding being whos looks put mortal men to shame.
But there he was, Darius en Kragin, one of a race of shape-shifting warriors bound to guard the gates of Atlantis, and kill all travelers who strayed within its borders.
Now Grace's life was in his hands, and Darius had to choose between his centuries-old vow and the woman who had slipped beneath his defenses and stolen the heart of Atlantis's fiercest dragon.
...source, back over of book...
This is not my favorite Gena Showalter book, but I don't want to be all down and out and hard on her. She's putting out multiple books a year - many of which I like. And it is more than I can say for some of my other favorite authors ...cough couch - Stephenie Meyer, Karen Marie Moning - cough-cough.... I have the other books of the Atlantis series, I'll be picking up another one shortly...and I'm sure you all will hear about it!