I'm Rob (not my real name). I have a younger sister named Emily (not her real name). My sister and I have always gotten along well, but one day something happened that completely changed our relationship.
I was bringing a basket of laundry to Emily's room. The door was closed but not locked, and I didn't bother to knock. When I opened the door she was naked and spread eagle on the bare mattress rubbing her pussy. She shrieked when I came in and because she didn't have any sheets to cover herself with, she just covered her boobs with her arms and pinched her knees together.
I quickly dropped the laundry basket, closed the door, and ran over to the side of the bed. She was so embarrassed that she started to cry. I put my hand on her hip and gently told her that it was perfectly normal for girls her age to have these feelings and that masturbation was something to enjoy and not be ashamed of. This seemed to calm her down a little, but she still kept crying and I began to feel really bad for her. I then said, 'You know, we could try doing this together sometime.' I was fully expecting her to say no, but she nodded her head in agreement. This also made her stop crying, so I dried her eyes with my T-shirt, let her get dressed, and then helped put her laundry away.
The next time our parents left us alone together, we both knew it was time. We ran to my bedroom, took off our clothes, and sat on the bed next to one another. I put my left arm around Emily's shoulder and my right hand over her left breast. Her heart was practically pounding through her chest. I told her to relax as I gently stroked her shoulder, all the while admiring how soft her skin felt. I could feel my hard-on building as she calmed down.
I had Emily lay back widthwise across the bed with her legs spread and her butt and feet up on the edge of the mattress. My fingers started searching through the folds of her vulva until I found her clitoris. I started to rub her clit with my left hand while the fingers of my right probed the inside of her vagina. Her clit poked out through the hood and started to elongate. Her pussy was tight but not too tight, and was also starting to get a little wet. I pinched her clit with my left thumb and forefinger and stuck my right index and middle finger all the way up until I found her G-spot. I noticed that Emily wasn't doing anything with her hands other than supporting her hips, so I told her to cup her breasts with each hand.
I began to roll Emily's clit around with my left fingers while sliding my right fingers back and forth across her G-spot. I could hear Emily starting to moan and gasp with delight. I started to quicken the pace and Emily's breathing got heavier. I moved faster and faster and she got wetter and wetter inside. Finally, the walls of Emily's vagina clamped down on my fingers. She let out a very loud gasp as she arched her back and started to shake all over. Her butt almost slipped off the edge of the mattress and her pussy juices began to ooze between my fingers and down the back of my hand.
When Emily recovered from her orgasm, she sat up and said, 'Now, it's your turn.'
I laid back lengthwise on the bed with Emily kneeling on the floor beside me. My rock hard penis was pointing straight up in the air. Emily gripped my penis with her right hand and started to stoke it. At first, she wasn't holding it hard enough, so I told her to grip it more firmly. Emily increased both the pressure and speed. It felt great and could feel my orgasm building. As she kept stroking, I yelled out, 'I'm about to cum!' Just then, 3 big spurts of semen came shooting out of my penis. They went straight up in the air, barely missed Emily's nose, and came back down on her right hand.
My orgasm made me feel light headed, so my head dropped back on the pillow with my eyes closed for a good 10 seconds or so. When I opened my eyes again, there was Emily, squatting on the floor next to me with this most precious smile on her face and cum all over her right hand. The sperm started to drip off her wrist and dribble down on her leg. We quickly jumped in the shower together to get cleaned off before our parents got home. While we bathed each other, we told about how much we enjoyed our orgasms together.
Emily and I would enjoy many more masturbation sessions together, but the first was always the best. I love my sister. She is such a sweetheart.