Masturbating with Sis

...I couldn't stop thinking about it. Walking behind the barn I kept thinking about what happened just an hour ago. "She was completely naked... I saw everything, yet for such a short time".

Just an hour ago I opened the door to our room carelessly without even thinking of knocking. There I saw my older sister completely naked facing me. It all happened so fast... she screamed and I started running.

The images are still crystal clear in my mind. Her pale skin, her small breasts, her round pink nipples, her small batch of pubic hair slightly covering her... girl parts. My heart skipped a beat. That was the very first time I've seen a girl naked in my life. Here in the countryside there aren't really any other young people besides me and my sister. Back in school the other boys would often talk how they sneak around the girls changing rooms and peek inside. I never gained the courage to go peek with them.

Again the image of Karri's private area flashed in my mind. "I have to stop thinking about it... IT'S WRONG, SHE IS MY SISTER..." I thought to myself. But it was useless my head was in chaos, shortly after that thought my mind was again filled with images of her exposed slender body. I felt my penis getting harder in my shorts.

Before I knew it I was walking around in circles in the yard. I don't know how much time had passed... 15 minutes? 30 minutes? An hour? It didn't matter anymore, I was completely lost in thoughts to care.

Suddenly someone grabbed my shoulder from behind, stopping me in my tracks. My heart skipped a beat. "It's her" I thought "She must be pissed I saw her... My life is over!".

After a moment of staying completely petrified I turned around. Karri was standing in front of with an innocent face with blushed cheeks. She was wearing a sleeveless white shirt and a short red skirt. I also noticed she wasn't wearing a bra... I was able to clearly see nipples poking out from under her shirt.

I stared blankly at her for couple of seconds while she was trying to say something. I felt strangely guilty in that situation so I didn't say anything.

"Y-you saw it... d-didn't you?" - She said with a quite stuttering voice.

I slowly nodded in reply. I noticed her face becoming even redder.

"Then show me yours as well!" - She said raising her voice. "It's only fair since you already saw mine."

I felt how my heart picked up speed and started racing in my chest.

"What, but it was an accident, it's not like I owe you something!" - I blushed and felt strange.

"C'mon... show me your dick. I reeeeeeally want to see one." - A smile appeared on her face.

I didn't reply. I didn't resist. I didn't run. I didn't move a muscle. Her hands were already on both sides of my shorts. With one fast pull she stripped down my shorts and my underwear together. A feeling of embarrassment ran through me. There I was standing with my junk in front of my sister's face.

"I imagined it bigger." - She said. Her smile became even wider. "Does it get any bigger than this?"

Back in school when changing in the locker rooms and in the showers I noticed that my penis was smaller than most other boys, but nobody has pointed that out 'til now.

"Of course it does! When I get excited it becomes hard and big."

"Show me"

"I can't... its embarrassing..."

"I bet you got hard when you saw me get changed, didn't you?" - She reached out with her right hand and grabbed my flaccid dick with her thumb and her index finger.

My whole body twitched. The images from earlier began reappearing in my head as she started stroking my penis back and forth with her fingers. I closed my eyes and saw her once again. Her round breasts with two very small and nipples facing in two different directions. The slit between her legs, narrow and tight, gently covered by thin brown hairs.

I opened my eyes. My penis was already completely erect in Kerri's hand. Her warm fingers touching my private parts felt better than anything I have experienced in my life.

I looked at her face. She seems be to enjoying it a lot as well.

"Usually I stroke it until I feel really good."

She giggled. Then she stood up and brushed the dirt off her knees.

"We girls do it too you know." - She giggled again like a little girl.

Then she pulled down her skirt. Under it she was wearing white panties with a small red ribbon on top. I noticed a small wet stain on her panties. Throwing her skirt aside, she quickly pulled down her panties and held them in front of my face.

"Here this will help!" - She placed down her panties on my dick. I felt the sticky stain on the tip of my penis. "I once heard about a guy who loved to jerk off with dirty panties."

I can't say they didn't feel good.

She was now standing in front of me completely bottomless. Kerri then slowly sat on the grass and opened up her legs facing me. My sister's vagina was completely exposed. I stared into it and felt my cock throbbing slowly lifting up and down the white pair of panties hanged on it. I grabbed it and started to jack off. The silk rubbing in my penis felt great. My eyes were pinned at her vagina.

She then started to rub her vagina as well. Slowly up and down her slit. Sliding her middle finger in between her pink vaginal lips from bottom to top and from top to bottom she teased herself right in front of me while watching me masturbate.

The thought it self was enough to make me almost cum.

My penis was harder than ever before. It was definitely the best I have felt in my life. Kerri also seemed to be enjoying herself. She was sweating and moaning quietly, her nipples were clearly visible from under her shirt now.

She slowly lifted her lower body from the ground. That moment I got a good view of her butt as well as her dripping wet vagina.

"L-look... I'm about to cum..."

Then she used her index and middle finger to spread her vagina apart. It was dark pink on the inside. Kind of disgusting, but also very hot. "My sister's most private area! Nobody has seen this but me!"

That was the moment when I reached my climax point. My load shot through the thin fabric of Kerri's panties and sprayed all over her leg. Suddenly all of my strength left me. My hand, covered in sticky fluids, slowly released my penis and I leaned back on the wooden fence behind me.

Biting her lower lip, Kerri covered her vagina with her right hand and closed her legs. After slowly getting up still covering herself she reached with her other hand to retrieve her panties. Suddenly feeling shame again I did my best to cover up my manhood.

After grabbing her skirt she smiled at me for a second and then ran back in the house. After standing motionless for about 5 minutes with my, now soft penis still dripping sticky fluids, I finally pulled my shorts and ran back inside as well thinking "What have I done?"...