“Not tonight because they got busted last weekend.  So I am really bored.”

“Same here, want to go night swimming?”

“Of course,” I said excited at the thought of seeing her in a bikini.

We both went upstairs to our rooms to change into our swimming garb.  I just threw on some boxers and athletic shorts.  I was done first and told her I would meet her outside down by the pool.  She took forever, but it was well worth the wait.  I was sitting on the side of the pool when she came down in her new bikini that barely covered her teenage body.  She looked so sexy and I couldn’t wait to see her body shimmering with the beads of water from the pool.

Naturally she was scared to go in because she thought it might be cold.  So of course, being her older brother, I opted to push her in to see what I wanted.  I then followed by jumping in.  What I saw when I jumped in made my week.  When my sister surfaced in the shallow end, she came out of the water like in one of those hot movies or photo shoots.  She was 13 but looked like a 21 year old swimsuit model with perfect abs.  She ran her hands through her silky wet hair and her body glistened with beads of water that should have been evaporating off her hot skin.  But amazingly this was not the best part.  During the struggle of me pushing her in, her left boob had popped out just a little so that I could see her nipple.  Kate had small nipples that were a little darker than the usual pink.  They matched well with her perfectly tan, but not too tan, skin she had achieved this summer by the pool.  It was also awesome that she had no tan line.  Not much of her boob popped out, just a little bit of her nipple.  Immediately she noticed and shoved it back in, but not without a slight blush.

“Jeeze Kate, control ‘yourself,’” I said with a little chuckle.

“Shut up Jake, its not funny!”  She answered with a huff as she got out of the pool and wrapped a towel around her amazing body that I now had more respect for.  Those nipples really did make her perfect tits complete.

“Sorry Kate I didn’t mean it.”

“Yeah well it’s your fault anyways,” she said as she turned to walk into the house.

“Whatever, I am going to take a quick shower before bed.”  I said as I followed her inside.  She did not respond so I assumed she was angry and a little embarrassed.

It felt good after a long day to put some music on and hop into a hot shower.  Steam was rising everywhere because of my little pool experience in chilly water.  I couldn’t get Kate out of my head, no matter how hard I tried.  Before I knew it, my cock was hard as hell.  I don’t know if I had ever been that hard.  I had seen what I had been dreaming of for years, my sister’s nipple.  So I decided to start jerking off in the shower.  Why not?  There was no chance of me getting caught.