Car Sex Scene

I love this movie, but just started laughing...after they "do it" and they're in the backseat of the car, Diane says to Lloyd that he must be cold because he's shaking, which he denies...this girl was valedictorian but obviously never looked up "orgasm" in her huge dictionary. Plus, how creepy was it that she told her dad upon her return home that she had sex with him?!