What a fascinating thread. I normally try and stay out of these things but I think my experience might be relevant.
My husband is a spanker and more. He likes to spank and use other implements with a bit of mild BDSM thrown in, with consenting females in his playroom. Often there is no sex...
On another occasion I was spanked, punished and face-fucked in the back of a break-down truck, in a laybye just off the M6 after my car had broken down. It's part of one of the punishment sessions I've written up.