I guess this story needs to start with an introduction of sorts. I am 30 years old and I am about 215 pounds athletic build with a shaved head. I have always tried to stay fit and enjoy lifting weights. Anyway, with that aside I have always found my mother in law Beth to be quite attractive for a woman approaching her late 50's. She has beautifully large breasts, my guess would be 46DD, a shapely figure, grey hair and nice legs for someone her age.
Anyway, I was at her house one day, painting her downstairs for her and my father in law. My wife was out of town and my father in law was at work for the day, so it was just the two of us. Beth called downstairs and asked if I needed a drink or anything, I responded that I was okay. She let me know she was going to take a bath and to answer the phone if it rang. Before I go any further I guess I should describe that Beth is not what one would expect to be a sex machine, as she is quite conservative and always keeps those huge tits concealed by sweaters and baggy shirts. This of course was what she wearing today, a big baggy shirt so I didn't really think anything would happen, especially not what was going to happen.
I could hear the water running, for some reason the fact that she only takes baths and not showers always seemed to excite me a bit. So the water turned off as I continued my painting duties. About 15-20 minutes passed when I heard Beth call down to me.
"Ben can you come upstairs for a second." Beth yelled
I trotted up the stairs and went to the bathroom door and knocked.
"What I can I do for you?" I said figuring she needed me to call her husband or something.
"Can you come in and hand me my razor, I forgot it in the cupboard." Beth said.
I gulped and nervously said "Are you sure?"
"Of course. I'm covered just come on in and grab my razor please." She responded.
I slowly went in the bathroom and could see her in the mirror, she had her right arm across her breasts and smiled as I came in. She pointed at the drawer where her razor was. As I was getting her razor I glanced up at the mirror trying not to look obvious. Her skin looked so smooth, and I could see the tops of her breasts pushing up over her arms. I turned and handed her the razor and noticed she had a washcloth over her pussy. I could just imagine what her pussy looked like. Most likely hairy, as I imagined that she and Jim didn't have a lot of sex. I had already said I felt she most likely wasn't a real sex fiend.
So I gave her the razor and turned to walk out, she stopped me with her next phrase.
"Could you just wash my back for me please?" I stopped and could feel my cock do a little jump in my pants.
"Really?" I said trying not to sound too excited.
"It will only take a second." She responded. I walked back over and went to grab a cloth from the counter. She again shocked me "No just use this one." She said as she held up the cloth that was covering her pussy. My head was swimming, could this really be happening? I grabbed the cloth and quickly glanced down trying not to be seen. I was shocked that her pussy was so neatly trimmed. Very short grey hair covering her lips, god my cock was starting to poke out. I went behind Beth and slowly began washing her back. I looked down and could see her ass pressed under water and it looked nice.
Beth spoke up " A little lower." She leaned forward and I got an even better view of her ass. I had totally forgotten about my now rock hard cock as I was staring at my mother in laws naked back and ass. I was snapped back in as Beth leaned back and said thank you. I didn't want it to stop and then I noticed Beth was staring at my cock.
"Well now, do you like my old ass do you?" She said still staring.