Patty Simcox is your generic popular girl…except she's nice. Patty Simcox runs for student government, is a cheerleader, and is a killer dancer. Did you see that forward flip during the hand jive? But she's nice.
We're repeating it because in movies, the popular kids are usually the mean ones.
That's not to say that Patty's perfect—she's a mere mortal trapped inside high school, after all. And she makes a rude comment about Rizzo late in the film.
PATTY: That's the one I was telling you about.
"The one" means "the pregnant one." Patty shames Rizzo for being pregnant or promiscuous…but, to be fair, Rizzo makes fun of Patty a lot over the course of the movie, so we feel like this evens them out a bit.