Why not? Ask yourself that question at the end of this story.
My first wife had two younger sisters. Sarah was 15 months younger than her big sister and Sally was 3 years younger. So when I got married to Jenny, Sally was a very innocent-looking 18-year-old.
Sally had concentrated on her studies and had not been with or for that matter been out with any boys. She just didn't seem interested in them, but she had always treated me with affection and had even tried to catch sight of me naked on several occasions whilst I courted and slept with her big sister. Sometimes she even seemed to try too hard to catch me with tackle out, so to speak.
One morning, when their mother was away for the weekend with friends, Jenny had gone to the bathroom. The bedroom door was open and I lay in the tangled crumpled sheets with only my legs covered. My mind was replaying the night's activities of lovemaking with Jenny, and I stroked my cock in fond memory of the pleasure we had given each other. Lying there on the bed slowly wanking my erection with my eyes half closed, I became aware that I was not alone. Through the crack between the half-open door and the doorframe I could see Sally peeking at me, seeing me playing with myself.
"Like what you see, Sally?" I said softly, so as not to scare her away.
"You can watch if you want. Come and get a closer look. Looking only, OK?"
The spying eye vanished from the gap and Sally's head appeared around the door. She smiled and walked into the room, not taking her eyes off my prick.
At that moment we heard the click of the bolt on the bathroom door and Sally disappeared like lightening, fleeing back to her room. Jenny walked in with a towel wrapped around her and smiled, seeing me lying naked and ready for her. As Jenny made love to me I imagined what it would have been like with Sally, so very young and so fresh.
The thought was arousing from several aspects. Sally was young, but I knew her well, even loved as a sister, and most importantly and therefore adding to feelings of guilt, she was completely off-limits, untouchable. But she did seem to be fascinated, almost obsessed in fact, with seeing me naked. Well, if not naked entirely, at least seeing what my cock looked like. Anyone who thinks young people don't have impure thoughts should look back to their own years during puberty.
The years passed, and Sally would always get me to stroke her neck and shoulders when we watched TV as a family. It was all very innocent but I knew that touching Sally was not innocent in her imagination.
After Jenny and I got married and moved out to the country, Sally would come and stay with us for long weekends, and she always seemed to flirt with me whenever Jenny was out or in another room. I found these games very arousing; the glimpses of cleavage, thigh, knicker-clad bottom or crotch added to the temptation. Sally would always call me for some reason or other when she was climbing the stairs, and at these times the flesh would be flashed. If Jenny was out I would stand transfixed at the foot of the stairs whilst Sally gave her little show. I never dared make a move from fear of what would happen if I were caught or if Sally decided she didn't like my approach. For Sally never did say a word or invite me to get closer.
One weekend when Sally was down to stay I was making love to Jenny in our bed, she was being quite noisy as I pounded her hairy hole. -One thing about Jenny was she could never keep quiet- . But as she drew breath at one point and so was silent as I held myself ready to drive my hard cock back into the hilt. I heard a whispered request from across the landing, although very quiet.
"Again, again do it to her again." Sally was enjoying the sounds of our passion and I could imagine her lying on the bed in the next room less than 10 feet away, her night dress pushed up around her waist as her hands rubbed her quim. That for me is such a delightful vision as a woman pleasures herself to orgasm whilst her mind plays a perfect fantasy.
One thing Jenny never approved of or for that matter watch were blue movies, and one weekend, when Sally came to stay, I had borrowed a copy of 'Debby Does Dallas'. Jenny protested.
She said, "You can watch it, but I won't!"
Sally asked her sister, "Can I watch it?"
and Jenny replied very angrily, "I don't care what you do Sally, you're over 18 so can do what you like!"
With that, Jenny stormed out of the lounge and stomped upstairs to bed. I was a little shocked and looked at Sally, who sat on the sofa wearing only a long cotton nightshirt.