Summary from back cover:

La Belle Du Jour

With the letter breaking his engagement, Stephan Kirton's hopes for respectability -- and his chance at happiness -- went up in smoke. He supposed it was inevitable; his travels abroad, his "interaction with the lower classes", had put him beyond the scope of polite society. Oh, those and the fact that he was a bastard. He could still find consolation, though. Ormstead Park was a place for dancing and flirting, for drinking and gambling... and those came before less innocent sports. It was a place where he could find a woman for the night. Instead, she found him.

He didn't recognize her at first; real ladies didn't come to Lord Duncan's masked balls, and this young beauty -- as he recalled from his youth -- was just that. Her descent into this netherworld had brought her within reach, yet this was no girl of the day. Annabelle Winston was sublime. And if he had to trick her, bribe her, dare her, or get her drunk... if he had to protect her, server her, save her, whatever -- one way or another he would make an honest woman out of her. And she would make a happy man out of him.