I love to do it, and have it done to me. Nothing like listening to her moan as I run my tongue around her asshole.
I love woman on top because then I can caress and admire her body and do things like suck a nipple.
Let me count the ways.
In a parked car on a residential street, in the front seat with her sitting on my lap. I don't think anyone saw.
At sunset on a bench in a park with no one around. I opened my zipper and she sat on my lap (wearing a skirt) with her back to me and rode me.
On a sunny flat rock at a local nudist spot on a Sunday morning. We thought no one was around, but after we were done we noticed a guy peeking from behind a bush. I guess he had a free show!