We've travelled to a beach town as a gruop tour along with few friends of mine with their wife too. One night me and my wife foreplaying being fully nude. We've became so horny and started to have mutual masterbating. Both of us has been closed our eyes and enjoying the extreme pleasure. Suddenly my wife opened her eyes and saw one of my friends was standing standing inside our room. She's just pressed her legs together and hide her boobs with her hands and said oh my God. I've opened my eyes and became so embarrassed. He said with laugh that we've forgot to locked the door, he just wanted to pass sometimes gossiping with us. I asked him how long he's stayed here, he replied may be ten or fifteen minutes. We both are be sure that he's watched every hidden parts of our body. That's so embrassing really. Still my wife ran away from him whenever she's been in front of him.

I'm not sure that "caught" is the right word for my situation but I've had sex hundreds of times in public places (parks, beaches, etc) with others around.