My sister and I loved to play little made-up games, and even though we were both 18, we got pretty immature with each other sometimes. Maybe it was because we were homeschool by our super christian parents, but we didn’t know a lot of what other kids knew. So, when we saw Mom and Dad wrestling in the bedroom, we decided to have some fun and do that, too!
"No, wait! We need to take off our clothes! Mom and Dad were naked!" my sister said. I agreed, and we both got naked. I soon realized that I was staring at my sister’s breasts and vagina (our parents thought that hair trapped germs, so we were both shaved down there). I noticed that she was staring back, at my penis hanging between my legs.
"What, uh, what was it again that they were doing?" I said to her to get rid of the tension.
"Oh, yeah!" she giggled. Back to fun! "Well, Mom was like this, and Dad was sort standing like here…"
We figured out the position, and started to imitate them, performing their groans and gasps as well. But I noticed a change.
"Uh oh…ow!" I said.
"What is it?"
"My penis is getting all hard, and it’s hurting!"
"Let me see," she said. She grabbed me by the base, and surprised me. I accidentally let out a moan of pleasure.
"Are you okay?" she asked. "Does this make it feel better?" She stared to stroke my penis a little bit.
"Oh…yeah, yeah it does." Wow, I never knew my sister could do that! She continued to stroke me. 
"Is it almost all gone now?" she said.
"It’s…kind of," I said. "It doesn’t hurt, but…I think you should keep at it." She continued, faster and faster.
"Whoa," I said. "Wh-whoa, that’s amazing! Don’t stop, something’s happening-nnnggg!" I cut myself off as something white and liquidy started coming out of my penis. "Aaaah…aaaahh, that’s incredible!" I said. "Oh my god, sorry!" I realized, looking down at my sister, that I’d covered her breasts and stomach with this stuff. "Sorry!" I moved away. "I can get something to clean you up with!"
She seemed amazed, and she was looking at it with fascination. “No, it’s fine…” she said. “That’s incredible!” She picked up some of the liquid on her fingers. “Wow…” Looking over at me, she said, “Well now I have an ache down here!” She pointed at her vagina. “Can you help with that?”

My sister and I loved to play little made-up games, and even though we were both 18, we got pretty immature with each other sometimes. Maybe it was because we were homeschool by our super christian parents, but we didn’t know a lot of what other kids knew. So, when we saw Mom and Dad wrestling in the bedroom, we decided to have some fun and do that, too!

"No, wait! We need to take off our clothes! Mom and Dad were naked!" my sister said. I agreed, and we both got naked. I soon realized that I was staring at my sister’s breasts and vagina (our parents thought that hair trapped germs, so we were both shaved down there). I noticed that she was staring back, at my penis hanging between my legs.

"What, uh, what was it again that they were doing?" I said to her to get rid of the tension.

"Oh, yeah!" she giggled. Back to fun! "Well, Mom was like this, and Dad was sort standing like here…"

We figured out the position, and started to imitate them, performing their groans and gasps as well. But I noticed a change.

"Uh oh…ow!" I said.

"What is it?"

"My penis is getting all hard, and it’s hurting!"

"Let me see," she said. She grabbed me by the base, and surprised me. I accidentally let out a moan of pleasure.

"Are you okay?" she asked. "Does this make it feel better?" She stared to stroke my penis a little bit.

"Oh…yeah, yeah it does." Wow, I never knew my sister could do that! She continued to stroke me. 

"Is it almost all gone now?" she said.

"It’s…kind of," I said. "It doesn’t hurt, but…I think you should keep at it." She continued, faster and faster.

"Whoa," I said. "Wh-whoa, that’s amazing! Don’t stop, something’s happening-nnnggg!" I cut myself off as something white and liquidy started coming out of my penis. "Aaaah…aaaahh, that’s incredible!" I said. "Oh my god, sorry!" I realized, looking down at my sister, that I’d covered her breasts and stomach with this stuff. "Sorry!" I moved away. "I can get something to clean you up with!"

She seemed amazed, and she was looking at it with fascination. “No, it’s fine…” she said. “That’s incredible!” She picked up some of the liquid on her fingers. “Wow…” Looking over at me, she said, “Well now I have an ache down here!” She pointed at her vagina. “Can you help with that?”

(Source: hornycorner, via the-porn-stories)