"It was almost always on red eyes or overnights to Europe. We had one on a flight to Rome that was rather interesting. The couple didn't know each other at the start of the flight and, despite being on opposite ends of business class, somehow found a way to be in the same seat mid-flight. They decided to go at it sans-blanket, at which point we had to ask them to separate for the rest of the flight.On a different flight, I had a couple ask if they could stand in the galley for a few minutes to stretch their legs. They were very polite, and I said sure and went back to reading my book. I made it halfway down the page when I heard her moaning. I turned and looked, and the guy had her pinned up against my coffee makers with his hand up her shirt. I promptly told them to remove themselves from the galley and either finish up in the lav, or head back to their seats and keep their hands to themselves. If I can't get it on in my galley, no one can get it on in my galley.My whole take on it is, as long as you aren't doing it in public, you're being quiet about it, and you haven't been acting suspicious the entire flight, if you want to go have sex in the lav, then have at it. It's certainly not high on the list of places I'd want to have sex, especially given that the lav is cramped, smelly, and the liquid on the floor isn't water... But to each their own." ShinyCupcake via Reddit