I agree with sunshine as to the pretext of the song (coming back from college with a girlfriend), but I think she actually dumped him once they got there, and he was miserably eating alone when she put her number down on a napkin. Basically, he just needed a casual-sex bounce-back relationship to get over her. Thus, the Jessica Rabit sex character "rescued" him from the depression of getting dumped.
I agree with sunshine as to the pretext of the song (coming back from college with a girlfriend), but I think she actually dumped him once they got there, and he was miserably eating alone when she put her number down on a napkin. Basically, he just needed a casual-sex bounce-back relationship to get over her. Thus, the Jessica Rabit sex character "rescued" him from the depression of getting dumped.