University library while others where studying around. My gf was wearing a slightly long shirt and sitting on me as if reading a book in a tricky position. We were quite naked a few times... Later on we noticed we were in plain sight of an office in a uni building across. THIS WAS HOT.
My gf bend over quickly and swallowed my load when I was close to done... As expected, we were humping like rabbits at home after that.
The chapel, it has loud doors and gives you time to react... Often done oral sex there, and taken her from the back. Something that I cannot forget, a definite turn-on.
We thought about doing it in the park, drove around, it was too busy.