321G: POW Rescued By Woman Of The Night

I’m looking for a book I read many years ago, probably around the mid 1990’s, but I’m sure it was written much earlier than that, likely the early 80’s. From what I remember, it was a story about a POW or prison camp escape and/or rescue of a woman by a man who falls in love with her. I believe she may have been a prostitute and it may have been set during or adjacent to the Vietnam war era.

I remember one character, an older woman (perhaps a brothel Madam?) saying something like “she ain’t nothing but two hips and a hole” or similar when referring to the girls being prostituted.