Immortal Sins by Amanda Ashley

In a moment of madness, Jason Rourke indulged in a brief, torrid affair with a wizard’s daughter. That one night of unbridled desire brought with it a powerful curse. For three hundred years he has been trapped inside a painting, helpless to ease a thirst that grows stronger with every passing day. Resigned to his fate, he’s given up all hope of ever being free again until Karinna Adams buys the painting and inadvertently sets him free.

Jason has no designs on Karinna other than to use her knowledge to help him find his way in a world he no longer recognizes. But her beauty and her kindness are a constant temptation, firing his both his desire and his insatiable thirst. But an old enemy lurks in the shadows, threatening to destroy them both.