A guy dating a girl for her money?

Well this guy spent the whole year making fun of this girl in my class. It wasn't just him, all the guys made fun of her (but she is so ditsy that she doesn't notice). Her dad is the second best neurosurgeon in the state so they have a ton of money. Well I kind of liked the guy. Then she started liking the guy. The guy found out that she liked him and he asked her on a date. This really confused everyone because it was so random and unexpected. There are different stories going around- that she asked him on a date, that he asked her but then he backed out and was ashamed, and that he asked her for her money. I think that it was for her money but he didn't want to tell his friends that he asked her out. I still kind of like this guy. My respect for him dropped down though. What should I do?