Marquess of Diamonds by Tammy Andresen

This marquess is her surly hero in disguise…
Lady Abigail needs help. Her mother has great plans for her future but her lackluster performance as a debutante isn’t measuring up. Which is why she convinces her best friend’s brother to help her. A few dances is all she needs from the grumpy marquess and then the suitors will come calling. But the moment she steps into his arms, the trouble begins. He’s a former rake, after all, with more then a few tricks up his sleeve, and even if he doesn’t intend to, he captures Abigail’s interest from the first. What lady can resist tall, dark, and handsome? And when the other suitors do begin calling, she’s left to wonder if any of them will be able to hold her in their arms like the Marquess of Hartwell.

Lady Abigail is too sweet to be believed…
The Marquess of Hartwell, known to his friends as simply Hart, can’t believe that Lady Abigail is for real. She’s too kind, too gentle, and too sweet to be an actual woman. And he’s so jaded, even if she is that wholesome, she’d never want the likes of him. Except for underneath all that goodness is a person who shares his hurt and understands his past. And while Hart only agrees to help her to appease his sister, he finds himself, well, caring about Abby. Which is dangerous for this debaucherous rake. Worse still, the attraction between them grows with every meeting and that is deadly. And when he steals one kiss as a boon, he knows he’s in trouble, because the moment his lips touch hers, everything changes.
But as events out of their control begin to swirl around them, Hart must make a choice. Save what is good in this world and put his own battered heart at risk?