When I was about 15 I had no lock on the door of my room. I also had two giant windows looking into the back yard that had no curtains. One day, my little sister had four of her friends over, a bit of a party. But nonetheless I felt the need to rub one out. When I was sure that they all were downstairs, I whipped out my cock and started rubbing it. Later though, I heard one of them telling another, "I SAW MIKE GOING LIKE THIS WITH HIS PENIS." I immidiately, and stupidly, came straight downstairs asking what the hell was going on. One of them giggled and said "We saw EVERYTHING." Embarrassed, I walked back up to my room and played on my computer for a little while. Now even though these girls were a bit younger than me, I had wanted so bad to do something sexual of some sort to them. As you probably guessed, they came up to confront me eventually. But it was not quite what I had expected. The three who I had always wanted to fuck the most, Alexandra, Olivia, and another Olivia, were all standing there before me. I asked what they wanted and they said nothing, just moved foreward and sat on the bed with me. One put her hand on my chest and pushed me down. "We're gonna punish you for being so nasty." One of them started kissing me, which immediately shocked me. She and the two others held my arms down until I stopped struggling and realized that what was happening was actually a good thing. The two Olivia's then unzipped my pants and pulled them around my knees, causing my rock hard cock to bounce out. They both giggled and then began to kiss eachother, with my cock in between their mouths. After a while of this I couldn't hold back any more and I came in one of the Olivia's mouth (I still don't know for sure which one). They both laughed then left me with Alexandra, the one who was kissing me. She then slid on top of me and started rubbing my cock vigorously with one hand, still kissing me. I eventually came again on her stomach. She grinned, stood up, and left the room. We haven't talked about it since then and act completely normal when we see eachother.