Louis Tully is the geek of geeks. A little guy with big glasses, Louis is a tax accountant who's completely obsessed with being frugal. His choice of party banter is, um, lacking:
LOUIS: Everybody, this is Ted and Annette Fleming. Ted has a small carpet-cleaning business in receivership, and that's drawing a salary from a deferred bonus from two years ago. They've got fifteen thousand left on the house at 8%; so they're okay!
Somebody needs to give this guy a lesson in partying. And also a lesson in dating. He's head-over-heels for his neighbor Dana Barrett, but tries to court her by talking about his healthy supply of mineral water and nutritious foods. Needless to say, Dana isn't all that impressed and tries to dodge him as soon as possible.
Hilariously, Louis has much better luck with Dana after he's possessed by the terror dog Vinz Clortho and she's possessed by Zuul. When the two are finally united, they immediately get it on—though, sadly for Louis and happily for Dana, neither one will ever remember it. In the end, the only reward Louis gets for his adventures is a new tax client in the Ghostbusters and the honor of having Egon take a sample of his brain tissue. It's hard out there for a geek.