My experience took place back in the '60s. I was 18 then and still a virgin. Being rather shy, I had never been with a girl sexually, though I masturbated frequently to deal with my desires and fantasies. One summer, I got hold of some unique porn--called adult magazines back then--that I had found in an abandoned house in the neighborhood. One of the magazine's was called "Fanny Fetish" or something like that. It had lots of pictures of women's naked rears. I can't explain why, but it became my favorite among several I had.
One night I was looking at it, jerking away, when my older sister--I'll call her Dee--burst into my room without knocking. You can imagine my embarrassment and anger at the invasion of my privacy. Dee, who was 20 then and still living at home, thought it was quite a giggle when she realized what I was doing. Not only that, she snatched the magazine from my hands (which I was using to cover my erection) and teased me about my choice in porn. Of course, she wanted to know where I got it, and why I found fannies so irresistible. I stammered and gave her vague responses, before finally getting her out of my room. I should stop and say that Dee physically wasn't a knock-out. She wore glasses, was a bit plump and had a sassy, sometimes demanding personality. But she had a decent hourglass figure, was a bit buxom and a decent ass, which I hadn't paid much attention to until what happened next.
That night was ruined as far as any self pleasure was concerned and I was in a foul mood. I remained angry at my sister for the next few days, barely talking to her. But one night, she was walking back to her room after taking a shower in the one bathroom we had, and when passing my room, where I had the door open, she called out, "Hey Jimmy, check this out," and flipped the bottom of her towel, exposing her ass to me. She laughed and hustled down to her room before I could respond.
I remember being shocked at her brazen act, but also feeling a jolt: wow, my sister has a nice creamy ass, just like the women in the porn magazine! I began to feel a stirring in my cock and a sense of confusion. I didn't do anything that night, but I couldn't get the image out of my head.
The next time my sister took a shower, I purposely left the door to my room open and sure enough, she stopped, called my name, turned and flipped her towel up. This time, she gave her ass a shake and said, "add this to your fanny fetish!"
I don't know if my sister was hoping I would respond in some way, but as much as I wanted to do and see more, I was too timid to say or do anything. Quite frankly, she intimidated me and I didn't want to trigger her bad side, which could be ugly.
Well, I didn't have to wait long and I didn't have to take the initiative. The next night, the same thing, only this time, Dee came by in her towel and instead of flipping her towel to show me the sights, she came into my bedroom, shut the door, sat down on my bed and asked if was enjoying the show she had been giving me. I blushed deeply and said yes. Then she asked if would like to touch her ass. I remember looking at her, not sure if this was a prank or not.
Rather than wait for an answer, she bent over slightly, pulled up her towel slowly, exposing her round ass. "Touch it," she said. So I did. I remember feeling the warm skin (just out of the shower, so it felt good). I ran my shaking hands over her cheeks. Meanwhile I had an instant erection. Dee knew it and floored me by saying next, "you want to jerk off while you touch it?"
I didn't really answer, just fumbled with my pants, quickly pulling them down and began stroking my cock while rubbing my hands across her fanny. She warned me not shoot my cum on her ass because she had just showered. I quickly grabbed some tissues and barely made it. I was so over-whelmed and over-stimulated, I ejaculated in an instant. The whole time, Dee watched me. As soon as it started, it was over. She covered herself up, gave me a wink and said, "now you'll have a real fanny fetish," and walked out of my room.
I was in a daze after that. Not only had I touched another female sexually and masturbated in front of her, but it was my sister. I remember feeling very confused, as my sexual feelings collided with a sense of guilt that I shouldn't be doing this with my sister.
But lust quickly overcame any guilt I had. About a week later, my sister and I were up late, watching TV. Our parents had long since gone to bed. During a commercial, Dee turned to me asked if I was having more naughty thoughts about her ass since the incident in my room. Once again, I blushed badly and mumbled yes. Then she asked if I wanted to touch it again. Immediately, my heart started pounding and I felt an erection coming on. I nodded and she said to wait 5 minutes and then come up to her bedroom.
When I got upstairs, Dee was on her bed in her nightie. When I closed the door, she said I had to take my pants off. I stripped them off and she reached over and gave my my now-stiff cock a caress. I remember shaking when I felt her hand on me. I would have ejaculated rather quickly, if she kept it up, but she stopped and then turned around so her rear was facing me. She pulled up her nightie, and once again her lovely ass was right in front of me.
I didn't know if I would ever get another chance to do this, so I didn't rush. I gently caressed each cheek, running my hands up and down, over and over. As I did this, I could hear my sister sigh softly. Next, I kissed her cheeks and then pressed my nose into the top of her crack, breathing in the heady aroma of her sex and anus. My cock was throbbing so badly I ached. But I didn't want to go too fast. So I continued to caress, kiss, smell and as I did, I could not just hear Dee sighing, but could now see her fingers rubbing her pussy.
At this point, I couldn't wait any longer and I started to stroke my cock, grunting and breathing hard. Very quickly I could feel my balls tighten and was ready to cum. Spontaneously, I leaned in and pressed my cock into Dee's crack and ejaculated, pumping my semen into her cleft. And then my sister began to shudder and had her own orgasm, her fanny quivering from her spasms and contractions.
It was an amazing sight and an amazing sensation. And quickly it was over. Dee grabbed some tissue, wiped herself (and my semen off her ass) and pulled down her nightie. I put my pants back on and left without a word.
It never happened again. Much later, my sister said she felt guilty letting it go so far. But it's an experience I'll never forget and it was the first of many other fanny fetish experiences to come.