Kristy + Bart = ?

Bart and Kristy are good friends. They go to dances or to the movies sometimes, but they're not really boyfriend and girlfriend.
Or are they? Lately, Bart seems a little more serious. Kristy doesn't mind, exactly. It isn't that she doesn't like Bart--she definitely does. But she's not sure if she likes him like that. And what's going to happen to their friendship if they become a Couple?