I have been married for 6 years now and am very happy with my wife and our sex life. I have however always wanted my sister in law. She is 32 and hot. Two years ago my wife and I stayed in a motel with her and her husband. About 6am her husband got up to take a shower and my wife was still sleeping. With the bathroom light coming from under the door I could see my sister in law in the bed next to me. I started hearing the bed squeak a bit and noticed the sheets moving very fast. This went on for about 5 minutes until I saw her shake and take a deep breath.
A few minutes later her husband got out and she got in. Then it was my turn. When I took my shower, I left the door cracked a bit to let the steam out. When I got out of the shower I noticed that my sister in law was sitting next to the bathroom door doing her hair in the closed door mirror. I could tell that she could see me through the crack in the door so I decided to put on a show. I took my hard on and started jacking right next to her on the other side of the door. I shot my load into a towel and left it on the floor.
After I got dressed, she went into the bathroom to pee. She was in there for a few minutes and when she came out she smiled at me and finished packing. When I went into the bathroom I noticed that my jacking towel was opened up and all the cum was gone. I suspect she did a little jilling her self.
I have jacked off in her used panties many times, but that will be another story!