First sexual revelation

"Stand here, and when I close the door, take off your overalls and your underwear." He positioned me five feet from the door, and glanced at the knob  hole in the door (we were in the process of building our house),  recalculated, and repositioned me directly in front of it.
"Do I have to wait for you to say when?" I was confused, a little bit worried that I wouldn't understand his instructions properly, and would therefore lose my chance at making it in with my brother's cool friend.
"No, you'll be fine," he reassured me, "just make sure to stand there for a little while."

At four years old, I would have killed for the opportunity to be included by my brother and his friends, so when they had called me out of my room to "do them a favor", I was surprised, ecstatic, and honored. I didn't find it odd at all that the request was to remove my pants in my parent's room, even though I understood (from a brief lecture my parents had given me a few months prior) that my private parts were meant for my eyes only.

When he left the room, I stood in place and began removing my overall buckles, still wondering what the point of this exercise was. As I pulled my overalls off of my feet, and removed my underwear, I glanced over in the direction of the door, and saw an eyeball where the doorknob should have been. When the realization that I was set up started to settle, my cheeks flushed in anger and I pulled my overalls back up hastily, buttoning only my left button, and marched towards the door to let myself out. Without a word, I went back to my room to process my first quasi-sexual encounter.

My first sexual revelation was that whatever it was between my legs held the immense power of curiosity from my male peers. In my room, I removed my button, pulled off my overalls and my underwear, and spread my legs in front of my mirror. I was repulsed -- I mean, what was that hideous thing? How did they know that I have one? Was it some sort of deformation I possessed that my parents wanted to keep hidden from the world?