When my girlfriend and I were in our last year of high school we did not always have access to a car. Even though I was 19 and she was 18 we still lived at home. Usually we could use one from my parents or hers, but sometimes, depending on which shifts our fathers were working we might not be able to get one. It wasn't a big problem in the summer time as I would hitch hike to her house and then we would walk up town and go to a movie.
At that time there were 3 movie houses in the downtown core of the city and we often went to one of them for the main part of the date. We made out a little in the theatres but there were also ushers and if people got too boisterous in what they were doing they were likely to get expelled.
If that was what we had done for the night we often walked back to her house by cutting through the back of her high school and while there we often went up to the school wall where there were a few spots indented from the rest of the wall. Leaning against the wall we were relatively hidden from anyone outside the school property. People who like us were cutting through the property could usually be seen or heard before they would see us.
We wouldn't actually screw there but necking and some feeling up was usually in order. On one of those dates we were there making out a bit while standing and leaning against the wall. This particular night was nice and warm and my girl had let me undo her blouse, loosen her bra and allow me to fondle her tits and suck on them a bit. A man walked through the property and we didn't notice him till he was right beside us. When we did notice him she covered up quickly but Im sure he got a good look at her tits before she recovered. He didn't say anything and just kept going towards the downtown core the opposite direction from where we were going.
After he had passed she got dressed up properly again and we continued on our way to her home. I kissed her goodnight and started back for my own home. I was horny as hell after our interrupted time behind the school.