Vantage Point

I was about 15 or so when I started smoking cigarettes, so I would sneak out my bedroom window and got out back, I noticed my parents bedroom light was on so I ducked behind the shrubs we had there and was that their blind was all the way down, I was about a half inch from the bottom so I looked in...there was my mom totally naked less than 5 feet from me and my dad naked on the bed with his dick semi hard. I couldn't hear what they were saying because they had turned up the tv. My dad started stroking when my mom joined him, she knelt next time and took over,. A little background this was the early 80s.
.no internet porn but I had seen my mom's tits before on accident and that was the extent of my sexual knowledge. As I watched my dad get a handjob my mom leaned in and took him into her mouth...wait what..my mom?!?! I got so hard it hurt, my mom gave him a blowjob when all of a sudden she straddles him and gets on top...I couldn't take it anymore I unzipped and started jerking off...I didn't last long, I watched them fuck for about 15 minutes when I guess they both came. After that if I heard the volume on their TV go up I'd wait few then go to my secret spot behind the shrubs.