"Second Hand Rose" by Vickie Tern (VickieTern@aol.com). The man and his wife differ in their selection of friends. He figures hers are a bunch of snobs, and she gets embarrassed when he drinks to much and makes a fool of himself in front of her friends. They go to a "stuffy" party at her boss's house. He's a publisher, and since the book he's currently working on requires some research on anal sex, and since the husband is already making an ass of himself - well, they make him part of the plot.

This is a really bizarre idea, but the author carries it off well.