The first erect penis I was exposed to was from a horse. My parents took me horse back riding around 9 and as I was being lead around on the horse in the other side was a male horse mouthing a female and well I just had to look.
He was very long and as he dismounted her his penis sprayed all over.
At that age I knew very little but enough to figure out about what was going on.
Several years later we moved to a new home and my room was an converted attic wher I had various views from diferant windows.
About a month after moving in I was gazing at the stars and since and noticed the neighbors light turn on.
It seemed to be the bathroom on the second floor, I had the light off on order to seed the stars better and this gave me a better view down also.