My aunt Jennifer was only two years older than I was. As a result, we were pretty much raised as sisters, since we both attended the same schools, and my grandmother (her mother) watched us while my mom worked when we were little. So it was only natural for us to move into an apartment together immediately after I graduated high school.
One night, after we had been living in the apartment for a few months, Aunt Jen, a professional masseuse, offered me one of her absolutely divine backrubs. I gladly accepted, knowing that Aunt Jen would work all of the kinks out of my neck, shoulders, and back. Little did I know how many kinks she would work into them.
She led me gently by the hand into her bedroom and told me to strip to my red satin thong and lay facedown on the bed. I quickly complied, having no shame in front of her; since we had grown up together, we had shared beds and baths numerous times, so we had both seen each other nude. Aunt Jen was wearing her usual round-the-house outfit, a pair of black spandex shorts with a green stripe up the side of each leg, and a matching sports bra. I grabbed a pillow and lay with my head to the side as I anticipated Jen's gentle touch.
After I had made myself comfy on her bed, Aunt Jen straddled my hips, and her amazing hands began to work their magic. I felt myself quickly relaxing as Aunt Jen gently massaged and caressed my neck, shoulders, and back. I was so relaxed, in fact, that it took me a moment to realize that as her hands went up to my shoulders, Jen's body moved forward, and when they came back down to my buttocks, she moved backward.
At first, I thought nothing of it, chalking it up to Jen simply getting a better reach to give me a better massage. But after a while, the movement became very rhythmic, and faster as well! Puzzled, I said nothing, and the strange dance continued. Then I realized where her body was in relation to mine. As she rocked back and forth, it occurred to me that Aunt Jen's crotch was rubbing right on my tailbone. My aunt was getting herself off while she massaged me! My suspicion was confirmed when the massage stopped, and Jen's whole body clenched, she gasped quietly for breath, and I could feel her pussy quivering on my ass.
Still, I said nothing, and after a moment, Aunt Jen continued her massage, once again moving her body in time to her hands. Now knowing what she was doing, I continued to remain silent, but I realized that I could feel a growing warmth in my body. I was amazed that the thought of my aunt masturbating on my ass would turn me on, so I focused on the sensation of her body rubbing against mine.
Sure enough, I could feel my panties growing damp. Suddenly, Jen's hands were gone from my back, but her body continued to rock back and forth. I risked opening the eye that was turned up, and saw my aunt. Her eyes were closed, and she had pulled up her sports bra, exposing her small but beautiful breasts. Her hands kneaded them gently, and her fingers pulled at her round, pink nipples, which were now fully erect. It was the most arousing sight I had ever witnessed.
As I watched, my aunt let out a small moan, and one hand continued massaging her tit while the other slowly slid down her belly, then around to her tight ass. Out of the corner of my eye, I could see her sliding a finger down the crack of her ass, her spandex shorts drawn up tight into it. Lower and lower her finger explored, and then I felt it brush my pussy through my sopping wet panties.
I moaned involuntarily, which seemed to shock her, for she immediately stopped dead and jumped off of me.
