It all started a couple of months ago when me and my younger sister Jessica went over to my older half-sister Lissa's. I needed to get some yard work done for her since she recently divorced her husband and her two sons weren't ever around.
It was a hot day in the middle of summer, so I wasn't wearing a shirt while mowing the lawn. I'm a pretty average guy, about 5'10 and thin, I don't have much in the way of muscles, but I do have some. The girls were laying out in their bikinis trying to get some sun. They had the radio on listening to a mix of genres, while sipping some drinks I made them since I just started bartending at the beginning of the year.
After about an hour of pushing that damn lawnmower back and forth I finally finished. I wasn't quite ready to end my day outside so I decided to run up onto the pool deck where my sisters were sunbathing, and do a cannon ball into the pool in an effort to get them wet. Well, the plan worked brilliantly, they both got drenched from head to toe. They yelled at me, calling me a brat and I replied with a teasing laugh then sticking out my tongue. I then decided to invite them in telling them that since they were already wet they might as well.
As they got up I was glad I had my sunglasses on because I couldn't help looking each of them up and down as they stood. Jess had just turned twenty one a few weeks ago and her body definitely matched her age. She had a slender frame like me with a delicious v running from her hips to parts beyond. She was also blessed with perky b-cups that shimmered in the sunlight. My older sister Lissa, who was fifteen years older than my twenty three, had an athletic build. She was a huge fitness buff, she worked everyday and even boxed every few days. She got some good genes from our mother with her outstanding d-cups. I was brought back to reality when I heard them giggle as they jumped into the pool and each splashed me.
We swam around for a little while splashing and laughing, calling each names as we always did. Finally when all of our fingers and toes were pruned we decided it was time to get out. They went back to their chairs and drinks while I dried off and told them I was going to grill us up some dinner. Still in just my shorts I cooked some burgers hot dogs for us to chow down on. As Jess took a huge bite into her hot dog a big glob of ketchup dropped right onto her cleavage. I watched it fall and then almost started drooling as I watched her scrape it off with her finger and stick it into her mouth pulling it out slowly sucking all the ketchup off her finger in an innocently provocative way.
At this sight I could feel all of my blood rushing southward. We were finishing up dinner and I still couldn't get the thought of Jess sucking her finger out of my head, and as I stood up I realized I still had a raging boner. And I wasn't the only one, in unison my sisters said "well it looks like someone is excited about something!" I blushed and rushed into the house. I could hear them giggle as I went inside half embarrassed and half turned on.
I decide its time for me to get a shower to wash off all the sweat, grass, and chlorine left on my body. I walked out in my towel to go to the room with my clothes and as I walked past Jess and Liss, Liss' dog jumped on my and effectively pulled my towel down with him. Still being half hard from the dirty thoughts I had in the shower it didn't take me long to get full mast. I didn't react fast enough and they saw everything. I quickly grabbed my towel and wrapped it back around my waist, but it was too little, too late. I looked up to see both my sisters mouths open in amazement at my huge eight inch cock. I told them I was going to go take a nap since we were going to go out to our favorite bar tonight and I was tired from the afternoon.