When I was 24 and not yet married to my wife, we were in my mother and fathers house with a male friend of mine. They were supposed to be on holiday until the weekend and it was only Thursday. My then girlfriend was lay naked under me on the lounge carpet, as I was fucking her. My male friend was balls deep up my arsehole from behind. It was only when I heard my mothers voice saying "Maybe you should get unplugged, get dressed and go up to your room, before your father walks in". did I know they were home. My friend left almost immediately, but my girlfriend and I went to my room. My mother has never mentioned it to my father, nor has she said anything about me being bisexual. She does however sometimes mention my AC/DC moment when she's annoyed. My father always looks confused but never asks.