Have you ever been caught in the act?
As far as I know the only times I’ve ever been caught in flagrante was when I wanted to be caught, when the person was supposed to join in. A couple times I forgot to lock the door at gay saunas and people tried to barge in while I was fucking, but I don’t really think that counts in the same way as someone walking in on you at home.
There was one incident while I was a university student and sharing one of the rooms in the flat with another guy. I went out with some of my flatmates and got shit faced. Eventually we made our way home and I passed out in bed. The next morning I woke up, hung over as shit and trying to piece together the previous night. In walks my roommate, who closed the door when he realized I was awake. Apparently at some point during the night I had decided I needed to wank, and the poor guy had been in his bed, privy to the whole thing; he was not a happy camper. Once he finished ripping me a new one I apologized profusely for my drunken indiscretion and turned my attention to the more important issue of nursing my hangover.