One night my wifes younger sister was staying at our house and i went out for a smoke, as i was walking past the side of my house i noticed that the light in the spare room was on and as i passed i looked down noticing that with the way the blinds were turned i could see right into the room. my wifes sister wasn't in the room but i walked to the back yard and as i was standing there i seen her walk past the window in the family room. i couldn't hepl my self and walked back to the window of the spare room and looked in. My wifes sister walked into the room and closed the door. As i stood there she opened her bag and put her tooth brush away. I watched as she undid her pants and pulled them down showning a tiny black G-string and her skinny little b**. I have to admit she is a little skinnier than i like but has big boobs and at the time she looked great. She pulled on a pair of shorts and i figured the show was over. but as i stood there she grabbed her shirt and pulled it up over her head showing a nice lacy black bra barely containing her big c-cups. She then reached back and unclipped her bra, As she did she turned away from me she picked up her shirt and in my mind i was saying please, please please turn around. Almost as if she heard me she turned to face the window and my heart stopped. there she was topless with the firmest, roundest, most beautiful boobs topped with light pink areola about two inches across and hard little pink nipples. She walked over to the mirror and looked at herself lifting up onto the b**** of her feet and dropping back down watching them bounce. I pulled out my c*** and jerked off which only took about two minutes. just after i came watching her she put her shirt on and crawled into bed. I went in the house and was so h**** i got hard again and had sex with my wife. I have since had similar oportunities with my wifes best friend who is a little chubby but has huge E-cups, Two of her cousins who are both DD-cups and next week her mom is coming who is a very good looking 43 year old.