Remember back in the day (90s), some department stores would have those little changing rooms out in the middle of clothing departments like little cabins with nothng but a thin cheap closet-style door (the kind with the angled horizontal wood slats)?
On this little island in the middle of the St Lawrence during a day with heavy boating traffic...fully visible from the US side.
In the book stacks at the university library (thrill of possible expulsion added to the rush big-time).
Got a blowjob in an alcove at a museum before too, behind a pillar.
Fooled around at the back of a church (fucking would have been pushing it too far...just a quick finger-bang up under the skirt while getting stroked)