At prom, Finchie sees Stifler hitting on every girl in the place. Instead of confronting Steven he seeks revenge in (dirty, dirty, Katie) the crooner's mother. Chaos ensues.
At the hospital Stifler and Finch have a talk and realize that it could never work because they have too different of priorities: Stifler wanting to screw every girl in Michigan and Finch wanting to have a meaningful monogamous partnership.
Katie Mariie: Short. Like a relationship with Stifler.