I have divided this story into seven chapters. You can read them each individually or all together. Either way I hope you will enjoy my story.
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Chapter 1
I was 18 years old and in my senior year of high school. We lived in a quiet suburban neighborhood in a two level colonial. I was very shy, a late bloomer, and hadn't dated any girls yet. I had an older sister, Jennifer, who was 20 and worked as a waitress while she went to community college. She still lived at home to save money. She had a steady boyfriend, Mark, and when she wasn't studying she was spending most of her time with him.
Our parents were fairly strict and Jennifer hadn't started dating until she was 18. They both worked and usually didn't get home until after 5pm. Mom taught at the elementary school and Dad was an architect.
It was Monday afternoon and I was just getting home from school. I came through the garage door into the kitchen, threw my backpack onto the table and proceeded to go to my room to change. On my way through the family though I was stopped dead in my tracks. My sister was giving Mark a blowjob on the couch. They hadn't heard me yet and I watched her head going up and down. Then the hardwood floor squeaked beneath my feet. Her gaze turned to where I was standing.
"Oh shit!" she screamed muffled by Mark's dick in her mouth.
"Oh shit!" she screamed again quickly jumping up.
"I didn't see anything," I said already running towards the stairs.
"Sean!" she yelled.
"What?" I responded.
I could hear her telling Mark to go home.
"I'll be up in a minute," she yelled.
"Okay," I replied walking to my room.
I couldn't believe what I had just seen. Her mouth was wrapped around her boyfriends dick. Never could I have imagined her doing that. I knew she did stuff with Mark because I had heard them before but usually they were making out.
My sister is pretty. I always knew that. She is petite, 5'2"", 105lbs, with dark brown hair and has piercing blue eyes. Being a late bloomer I was still growing and at age 18 I was 5'7", 155lbs, with dark hair, blue eyes, and I was in good shape from years of soccer and baseball.
After what seemed like an eternity she walked in. I was standing looking out the window.
Embarrassed she said, "Sean. You have to promise you won't say anything to Mom and Dad."
"Yeah, that's cool," I replied.
Now glaring at me, "No seriously?"
"I said, it's cool. I promise I won't say anything Jen."
"Okay little booger. I didn't mean for you to see us doing that. So we are cool?" she asked poking me in the stomach.
"Stop that," I giggled pushing her hand away.
Poking again she asked, "We cool?"
"Yes," I replied trying to end the awkward conversation.
She then gave me a push and I instinctively grabbed her and tossed her onto my bed.
"Oh it's on brother!!"
Trying her best to make light of the situation she grabbed my shirt and pulled me onto the bed and swung me down on my back. We started tossing around for a few minutes, her short skirt twirling as we flung back and forth until she finally landed on top of me. She was straddling me and had my hands were pinned down. That's when I felt her hips moving, it was subtle, however I could feel the soft fabric of her panties brushing against my crotch. I instantly started getting hard.
"Do you know what I was doing to Mark?" she asked.
"Well yeah," I replied.
"How would you know?"
"Ah because I am 18 and not stupid," I responded now trying my best not to get hard with my sister on top of me.
Glaring at me she kept gently brushing her crotch across my dick.
"You little perv. You are getting a boner!" she said climbing off of me.
Looking down, I could see my dick was poking straight out against my jeans.
"You say anything to Mom and I'll tell her about your boner," she said squinting her eyes in a threatening manner.
"I didn't mean to... I'm... I'm sorry!" I tried pleading.
"Fine," she said flinging her hair around and walking out the door.
Walking out I noticed her lean legs, her very visible gap, and how she swayed her hips. I had never look at my sister this way.
That night I jerked off thinking about everything that had happened. From seeing her sucking Mark's dick to the feeling I had with her on top of me.
I didn't see her much the next couple days. Not until Thursday. It was 4:30pm in the afternoon and I was at the kitchen table doing my homework when she walked in.
"Hey squirt!"
"Hey," I said trying not to look up.
She got something to drink and I went to the walk in pantry to get a snack.
I heard her follow me in and she pushed her way in front me and reached up to the third shelf, at the same time pushing her butt out against my crotch.
"I can't reach it," she said trying to grab the cereal.
I stepped forward reaching up to grab it when I felt her butt pushing back on me. I couldn't move and I felt a tingling in my body. She put her hands on the shelf arching her back and pressed harder. My dick responded and I wasn't sure what do. Just like before, she didn't move much, but enough to rub me.
"I heard you the other night," she whispered.
"What do you mean?" I asked.
"I could hear your bed hitting the wall. Were you thinking me?" she asked.
"No!" I responded.
She kept pushing her ass into me.
"It's okay, I was also thinking of you while you were doing IT."
"You were?" I asked.
"I was. All I could do was think about was how big you felt."
She turned around and shyly asked. "Can I see your dick Sean?"
"I don't know. I guess so," I said embarrassingly.
"I want to see it." I unzipped my pants and pulled it out. My dick had really started growing in the past year or so and was now 7.5" and thick.
She gasped, "Oh my god. I knew it. You are so much bigger than Mark!"
Staring at me in disbelief she looked at it.
"Can I touch it?" she asked already reaching down.
That's when I felt her hand wrap around my dick and give it a tug.
"Have you been with a girl yet?"
I nodded no while trying make sense of what was happening. She gently began stroking me.
"Do you mind if I do this?"
"Um, I guess not"
Just then we heard the sound of the garage door.
"Shit!" we both screamed.
She put my dick back in my pants and zipped me up. I ran back to the kitchen table and she ran upstairs.
Mom walked in, "How was your day Sean?"
"Strange but good," I replied.
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Chapter 2
I didn't sleep much that night and when I got home from school the next day Jennifer was already waiting for me.
"You're not with Mark?" I asked.
Smiling she responded, "Not today."
She grabbed my hand. "Come upstairs with me."
She locked the door to her bedroom and walk over to me wearing a white tee shirt and short running shorts. She undid my zipper and swiftly pulled my jeans off. She pushed me back onto the bed with my underwear still on. She straddled me and expertly placed her crotch against my hard dick and less subtle than in the past she began grinding me.
Looking down at me she said, "I'm sorry Sean. I don't know why... We shouldn't be doing this."
Feeling the same anxiously about it I responded, "Yeah, I know what you mean."
She didn't stop though and her breathing got faster.
"You feel so big... and so hard though," she said grinding me harder. "Maybe... Maybe we just need to set some rules and boundaries."
She climbed off and lay next to me. Reaching over she rubbed my dick through my underwear.
Squeezing me while she talked she said, "Okay. First of all I know we shouldn't be doing this but I have been watching you grow for a while now and I kinda knew you were bigger down there. I know it's wrong in so many ways. Yet I feel a connection between us that I can't deny. Secondly, some rules. We can never have sex. Ever. Okay? Thirdly we only do what we are both comfortable doing and always respect each other. Okay?"
My dick felt so hard in her hands. "I guess so," I replied. "But I'm your brother and isn't that called insense or something?"
"Incest," she responded smiling.
"Yeah that," I replied.
Her eyes gazed the other way, "No one has to know. We'll figure things out later. Okay?"
"Okay," I replied.
"Good. Now take these off," she said helping me out my my underwear.
My dick sprung up and she looked at it seemingly forgetting anything that was said in the past couple of minutes. She grabbed it half way up the shaft and squeezed it.
"Sean. You really are big!"
She stroked me gently. "Does this feel good?"
"Yes!" I replied.
I was sitting back against the wall and she laid next to me. Looking down I followed the curve of her back past her thin waist and to her perfectly shaped perky ass. She was memorized by my dick and took her time. Her hands were small which made my dick look even bigger.
"You like this?" She asked.
"I do Jen," I responded shyly.
She squeezed harder and picked up her pace and looked up at me and asked, "Do you want your big sister to make you cum?"
Smiling she said, "I can't believe I just said that."
Moaning softly I nodded yes.
"Oh Sean you are so big. Just like I thought you would be. I want to make you cum."
Jerking me hard now I felt it coming. "Ohhh shit, here it comes Jen!"
"That's it Sean let go!!"
My body tensed up and cum flew out in thick spurts.
"Holy crap Sean. It's going all over my bed!"
Shooting straight up I released everything I had, "Ohhh... ohhh... ahhhhh!!"
Cum landed around my crotch, on my dick, on her bed, and all over her hand.
"Oh gross you little shit," she screamed. "Oh my god... you are cumming so much."
My breathing was fast and I had just had the biggest orgasm of my life.
"Sorry Jen!" I managed to say collapsing back on her pillows.
