When I was 15 years old I had a good friend of mine. We would spend many an afternoon at his house after school. He had a sister who was 28 at the time. Such a pretty face and balanced body. Of course being a horny teenager I had a big crush on her... :)

My friend and I would often go into her room to play videogames in her computer. She was not very tidy. More than once, we would notice a bra or two on or by the side of her bed. My friend would laugh at that. I would get excited...

 

A few times I got the chance to be alone in her room. So I did some exploration. My heart would always beat faster whenever I opened her dresser drawers. Her panties were not much of a thrill (cotton thongs and so on), but her swimsuits... Oh, that was something! She had several bikini sets. Some of them were made of Spandex, very smooth and shiny. Her musky odor emanating from them would drive me to those bikinis like a magnet! After a few encounters with her sweet things, frustration began to grow stronger inside of me because I had no time or means to have my way with them right there in her room. So finally one day I gathered enough courage and snatched a yellow bikini bottoms made from a type of Spandex that I really liked. It was so soft and shiny, and the bikini bottoms had good fabric coverage (just the way I liked it!) and a lovely thick double waistband. I thought about folding and hiding them inside one of the back pockets of my jeans, but was not sure about it, thinking my friend would notice. So I got into her bathroom, stepped out of my pants, put her bottoms on over my own undies and then my pants back on. When my friend returned we spent some more time together, but of course, I couldn't get the fact that I was wearing her sister's bikini bottoms out of my mind. I had to get home soon! So I excused myself and off I went.

 

Back home, my mom wasn't there and I knew I had a good two hours before she returned from work. So I took my time stepping out of my jeans, the bikini bottoms and finally my underwear. I lifted the bikini and caressed it with my fingers. My cock was hardening rapidly. Bringing the garment near my nose, I inhaled a little and savored her sweet sexy female scent. Now I was rock hard!! I wasted no time in pulling her bikini up my legs and over my sweet spot. Oh, what a feeling! It was a perfect fit, the shiny Spandex hugged my ass, balls and cock with just the right pressure. It felt so good, so right... I began caressing my butt over her bikini feeling the smoothness of the stretchy Spandex against the palms of my hands. When I repositioned my hands on the front over the hardness of my cock I felt an even more intense pleasure. My hands would cling to the fabric like it was a magnet and I began rubbing myself up and down, back and forth over her sexy feminine swimsuit. I had planned to take my time and make this sweet pleasure last quite long, but my hands seemed to have a mind of their own as I continued rubbing myself faster and faster each passing second.

 

I walked over to my mom's dresser mirror and admired myself grinding my hips forward, pushing my crotch against my hand that was rubbing my cock over my friend's sister’s sexy bikini. What a sight! Before long I felt I was approaching the point of no return, so I went for it, waves of pleasure and shiver traveling through my body, I felt my knees weaken as I erupted through the front of her bikini. I was in heaven and continued caressing myself through the garment for a few more minutes, until my erection finally subsided. Getting out of her bikini I decided to wash and dry them so I could store them in a hidden place. My decision was made, they were now MINE! I felt very relaxed, but when I began rinsing the bikini my cock started to get hard again. My lust for my friend's sister’s swimsuit was returning very quickly! I had to do something about it, I still had time, but the bikini was wet. After a few seconds of brainstorming I had an idea I thought was good enough to bring my thrill and erection back instantly!