Way back when was lucky to have the opportunity to join a sailing group and we had a 2+ week sailing cruise in the summer on the boat owned by the leader / adult sponsor of the group. On board that year were my GF, 2 of her 19/20 yo female friends, another guy and the 60 odd yo owner. One beautiful night my GF and I decided we would sleep in the cockpit in a sleeping bag. Being horny 19 yo's we became a little amorous with the typical kissing and fondling. We tried to remain somewhat controlled but the urges became too much and clothing was removed - just for better access and so we would not make any noise and wake the other 4 people we assume were asleep below, we rationalized. Well, that control did not last and soon could not take any more and I was on top of her and we were at it, as quietly as we could. The situation / stimulation was too much and it was not long before my GF clamped down on me in an intense orgasm, which triggered me well before I thought I was close. She was moaning / mumbling into my neck / shoulder as quietly as she could and I was whispering "Oh s%^&" repeatedly. If anyone has spent any time on board a boat you know how loud sounds on deck can be when you are below, especially at night. Being new to boating we had not learned that lesson at that point. Fortunately none of the others said anything the next day, but for the balance of the trip the owner demanded each of us sleep in separate bunks...