"Office Affair" by Mat Twassel (Mmtwassel@aol.com).

The narrator's love life with his wife has been mediocre up till now. He'd like more sex, but she's passive at best. But suddenly she becomes a veritable sexual dynamo. She suggests that maybe the secretary on the tenth floor would like to boink him, and then she demonstrates just how that young lady would perform the act. The next morning she sends him off to the office with the best quickie he's had in years.

Why would a woman change that way?

Hmmm... Just thinking about the answer to that question gives me a pleasant feeling in a nice place.