Paul Finch, despite his fear of using public restrooms, was always more mature than his friends - this cappuccino-sipping cad was an intellectual. A high school romance wouldn't work for him, and he ended up sleeping with Stifler's Mom, much to his frienemy's dismay.
In the sequel, Finch longed to be reunited with his cougar of choice. Early on, she fails to show up at the cabin on the lake the boys are staying in - but she does eventually show up and they continued their affair.
In American Wedding, Finch only plays a minor role, but once again he ends the film meeting up with Stifler's mom for yet another dalliance.
Ever the eccentric, Finch arrives in Reunion on a motorcycle, talking endlessly about his years spent traveling the world...