I was laying out by the pool catching some sun,not really thinking about anything in perticular, when my sister game out in one of her smaller bikinis.She was home from college for the summer and when she wasn't working she spent alot of time by the pool.It was easy to tell because of her dark tan and bleached out hair.She asked how I was doing and found a spot over in the corner of the yard where she laid out her blanket.The next thing I knew she was untieing the strings that held her top up and letting her tits fall free.She laid down on her back with her feet towards me and from my angle I had quite a view of her out stretched body.
It didn't take very long for my dick to start expanding inside my spandex suit and before long it was very evident I had quite an erection.The way she was laying I couldn't see her face so I knew she couldn't see me either, so I allowed my hand to slowly move back and forth over my bulging suit.
After a few minutes she turned over onto her stomach and untied the side strings to her bottoms and moved them out of the way allowing the sun to work on her hips.By now my cock was long and hard enough that it's head was almost out of the waistband of my suit and knowing that she couldn't see mee I pushed the suit down far enough that it sprang free.I was now lightly moving my fingers along the under side and over the tip of my dick watching my sister's ass as I did so.Being a what I thought was a normal 15 year old any chance I got to masturbate was fully taken advantage of, and this was like a dream come true. I was thinking it couldn't get any better than this when my sister thoughally suprized me by pushing the bottom of her suit down between her thighs completely exposing her ass to my eyes.I now had a death grip on my cock and was trying to keep myself from cumming and after the most self control I'd ever been able to muster did stop myself.I pulled my suit back up and tried to think of something else but it was hard to keep my eyes off what my sister had exposed.
For the next 15 minutes or so she stayed laying like that and I managed to keep away from my dick but my erection wouldn't go away. She moved her hands down to her suit bottom and I thought she was going to retie the straps but instead she raised her ass a little and pulled them off completely.Then she rolled over onto her back and for the first time in my life I was looking at a live pussy.She was only about 20 feet away and it was easy to see that she had trimmied and shaved her snatch so she could wear the small bikinis that see seemed to like.She had a very pronounced mound but her inner lips weren't exposed like some of the pussies I'd seen in pictures,she just had a set of pouty looking outer lips.My cock was now throbbing under my suit and again I pulled the waistband down to let it free.I was as excited as I'd ever been and it seemed alot bigger than I usually was.I could see pre-cum at the head as my cock bobbed up and down now that it was free of my suit again and I was afraid to touch it knowing I would cum instantly if I did.
Just then she quickly stood up and started my way before I had a chance to stuff my cock back in my suit.Before I knew it she was standing next to me looking down at my erection as it laid up against my belly.She was smiling and said that it looked like I was enjoying the show she had put on for her little brother and hoped that I had liked it .I was to excited and embarrassed to say anything and didn't even thing of putting my dick back in my suit.She pointed down at my cock and said that I shouldn't leave it like that to long or I would be in pain and that if I needed help to let her know.She told me to go ahead and finish jerking off and that if it was ok she'd like to watch as I did. Right then I didn't need an invitation to finish what I wanted to do.When I moved my hand down to my dick and started stroking she said she't help me along and she spread her legs and pulled her lips apart,showing me her swollen clit.It only took 3 or 4 strokes after that and I was cumming all over my stomach and chest.It didn't seem to stop and by the time I was finished there was cum over everything.
She looked down at me and smiling said that maybe we could do this again some time,then turned and walked back toward the house.
I've been waiting to see what she does next but except for bending over one time and letting me get a peak at her nipples nothing else has happened.I go out to the pool everytime shes home but so far she hasn't come back out.