My name is Erin. I”m 5″5, 115lbs, shoulder length dark hair, toned body from playing lacrosse and 38b breasts. I live with my parents and my older brother Billy. He is about 5″10, 180lbs, brown hair, played sports in high school so he”s got a pretty good body. We are pretty close in age and have a lot of the same interests so even though we are siblings, we consider each other close friends also. Billy has a girlfriend named Kelly that comes around quite often. She”s quite the looker at 5″1, 105lbs, medium length blondish hair, skinny but with a pair of big 36C breasts. I”ve never been attracted to girls but there was something different about Kelly that made her different from any other girl I”ve ever met. I often caught myself checking her out and have even day dreamed about a possible lesbian expiermentation with her.

The story begins one spring day at my house. My parents had left for a business convention and would be back in a few days, leaving the house to me, Billy and by default Kelly seeing as she would be over the entire time they were gone. I was in my room in the basement, bored out of my mind so I was just gonna go to the park and shoot a ball around but unfortunately Kelly parked behind me so I had to ask her to move it. I walk upstairs and don”t see her or my brother in the family room so I assumed they were in his room. I walked over and opened the door. The door was almost closed but I assumed if they were fooling around, they would have made sure the door was closed. How wrong I was. I walked in and instantly saw Billy and Kelly naked on his bed. They both stared at me with a look of shock on their face. I blushed and apologized and then my jaw dropped. Thats when I saw it. Between Kelly”s legs was a rock hard 8 inch cock.

I couldnt believe what I was seeing. A cock and balls, covered in a big, thick bush of black hair covering her genitals and expanding outward from the base of the cock. I finally figured out what made her so different from the other girls. She wasn”t one.

“”I can explain!”” Billy said. “”just shut the door””

In a state of shock I closed the door. As I was turning around Billy was trying to put his boxers back on and I could see his cock, just as big and hairy as his girlfriend”s.

“”Kelly is a male to female pre-op transvestite.