Anyone know the title of this romance novel?

About eight years ago my friend was reading a romance novel that I have been searching for ever since. All I remember is that it was about a girl pickpocket who gets caught by this noble guy and instead of turning her in, he makes her agree to pretend to be his fiance and visit his family with him (I think so they won't bug him about getting married). They dont like each other at first and bicker a lot. I remember there was a ball scene I read where the two main characters are argueing and I think she wore a pink dress (maybe). If anyone knows of a book that might fit this description, I would appreciate it so much! I have looked everywhere. Thanks!