Two of my students had sex in my classroom after school and I don't know what the fuck to do

Two of my students had sex in my classroom at the end of the school day. I was in the classroom but had my back turned and was looking at my computer on my desk, so I didn't realize they were doing that until they were both finished and "fixed" themselves. I don't know what the fuck I am supposed to do about this now. They aren't in trouble or anything, although I did tell them to never do that shit in my classroom again and told them to delete the video from their phones. I told my vice principal, but they just kinda shrugged and said "kids will be kids"?? But like I get that kids will be kids, I know that teenagers like to have sex, but just feels so disgusting that they did that in my classroom. Now I feel weird using my desk or sitting in my chair.