My mother in law lives with us. It can be annoying sometimes always having her around, but one time I found it rather stimulating.
She had broken her leg and had to wear a cast for a while. One day I came home from work while my wife was still out and her mom was asleep on the couch with her leg up on the back of the couch.
She had on a short nighty and no panties and I had a great view of a nice thick bush. I started rubbing myself through my pants while I just stared at that beautiful bush. She started to stir so I went into my room and started stroking to the image of her bush in my head.