Tempt the Devil by Anna Campbell

Any man in London would worship her. Yet Olivia is, quite frankly, bored of them all. Despite her many dalliances, she's never felt true passion, never longed for any lover's touch . . . until Julian, London's most notoriously wanton rake, decided to make her his mistress.

From the moment he first saw her, Julian knew he must possess her. And when he discovers her greatest secret, a scandal that could ruin her reputation and end her career, he knows just the way to use this damaging information to his most delightful advantage. He offers Olivia a deal with the devil: he'll keep her secret . . . if she allows him the chance to show her true ecstasy.

But Olivia must be careful, for Julian has a secret of his own: he will not rest until she is completely, shamelessly his.