One day when I was 19 I went over to my friend's house. I had to use the bathroom which is down a long hallway. Across from the bathroom is his mother 'Jen's' bedroom.
When I was walking out of the bathroom, I heard a moaning sound coming from the bedroom. Curiosity got the best of me so I walked to the open door of Jen's bedroom. I stepped inside the door to see Jen naked on her back on her bed, spread eagle, with her right hand pinching and massaging her nipples, and her left hand massaging her clit, alternating with inserting two fingers in her pussy.
I just stood there and watched, stunned for a moment. Jen has always worked out and has always had a toned body since I first met her. My cock was so hard and I was so horny I couldn't hold out any longer. I dropped my pants and my underwear to the floor and started to stroke my rock hard cock. With every moan from Jen it just got me hornier, so I just stroked harder and faster. I suddenly exploded and came all over my hand.
I muat have let out a few moans myself, because when I was through, I looked over and saw Jen looking at me and smiling. Jen then proceeded to continue fingering her pussy and came with a gush all over the bottom of the bed.
We both got dressed and didn't say a word. I never had the pleasure of seeing Jen masturbate again, but I will always remember that experience and smile whenever I see my friend.