Magic & Ménage à Trois 4: Falling for Eternity

Naomi enjoys a quiet, peaceful life. She has just finished medical school and her hours at the hospital take up most of her waking hours. Her only grievance is that she harbors feelings for her guardian, a mage who took her in when no one else would and kept her off the streets. She wishes that one day, he would return her feelings.
Her hopes are dashed when he asks to meet her and informs her that she is to marry a man she has never spoken to in her entire life. According to Nigel, she owes the dragon a life debt and in return, he has asked for her hand in marriage. She doesn't remember incurring such a debt, but her lack of memory of the event does not nullify her debt. So, she meets with the mysterious dragon shifter with the scar on his face and hands large and strong enough to circle her waist and pick her up as if she does not weigh a thing at all.
She finds herself falling fast and hard for the man. He makes it no secret that he desires her and shows her all the pleasures she has been missing out on when she was pining for a man who didn't care for her.
She is taken by surprise when, at the end of her date, she was kidnapped and thrown into a cold, wet cave.
"This is a test of your worthiness," claims one woman as she bounds her hands and ankles and leaves her to die.
Lost in the darkness of the cave with nothing but her thoughts and the shadows around her, she begins to remember the things that she had long forgotten, including an event that happened eight years ago that had changed her life forever.