Slow Dancing With My Mother-InLaw

My mother-in-law moved in with us for economic reasons a while ago. I set-up a mother-in-law apartment for her in our house. She is very grateful, and she lets me know in her own way.
My wife goes to bed early for her early work shift, which usually leaves the evening free for me and her mother. We both enjoy romantic music from the past, and we play the old big band music albums together in the evenings.
She likes to twirl and dance to the music, and I eventually asked her for a dance. That is when it started. She held me close to her and I pulled her closer. We danced tightly with each other, I could feel her soft body against mine, and it made me horny for her. I got a huge erection as we danced, with my bulging boner pressed against her soft belly. She grabbed my ass, and held me tight while she humped me to the music. My boner grew even more. At that point, I kissed her, on the lips, and gave her my tongue. She gave me her tongue and squeezed me tighter. We fell in love on the spot! She reached down to fondle my hard cock, and stroked it with her tiny hands. She could feel my cock throb in her hands, and she told me how much she liked that. She kept relentlessly stroking me. She finally made me cum in my pants in a huge cum explosion! She made me cum two more times that evening. She smiled and said I was a good boy for her each time, and she wants me to be her good boy from now on. I told her that I am hers to do with as she will. My cock belongs to her now.