This happened about a week ago. My sister is 15 (twins).
When I go to bed, I usually look up at my ceiling waiting for my eyes to finally close for about 30 minutes. I might think about what happened today and wonder how or why things happen or just daydream about what could happen. I don't usually dream perverted things. It just helps me go to sleep.
My sister and I have a very good relationship, partly because we are twins. Our whole family has a good relationship in fact. We had 'the talk' as a family and we always discussed things related to the talk. I may ask things like 'Wow, your breasts have grown quite a lot in the past year,' or she might say to me 'Why did you shave your pubic hair?' The reason we may ask or say these kinds of things is because we are so close, that we don't mind being naked in front of one another. I'm not saying I go naked everywhere and she just sees my shaved pubic hairs, she and I see each other naked like when taking a shower (semi-transparent shower curtain), coming out of the bathroom after taking a shower, getting dressed, and when in the bath. I may go and brush my teeth while she is taking a bath. She doesn't cover herself with her hands or move the bubbles to censor herself. She sees me naked when I go from the bathroom to the hallway to my room after I take my shower. Every once in a while we may comment on each other's 'features' and to us it is no big deal. The only time we would rather not see each other naked is when we are 'experimenting' ourselves.
I masturbate about three to four times a week and my sister has told me that she does it maybe once a week but hardly ever to an orgasm. I've always wanted to fulfil this dream of her having her first orgasm but never had the courage to ask since we didn't do this kind of thing together.
My sister is about a 35-25-36 (I overheard her say this at a tailor's store) so you can probably imagine that she has a nearly perfect body. She has beautiful tits and likes to shave her pubic hair in funky shapes. She even got my parents to buy her an electric shaver that had a smaller razor so she could make out words. She is by far the best sister I could have.
I have a similar looking body (except the boobs of course!). Our stomachs look the same, shoulders, and even our feet. My penis is about six and a half inches long and five and a half inches around. It has a massive upward curve and a distinct looking head. My scrotum is pretty dark and I sometimes shave my pubic hairs (I don't like to keep them too long).
As I said earlier, I like looking at the ceiling before I go to sleep. Well, one night, I saw this figure creep into my room. I thought maybe it was my mom putting away some clean clothes but I was wrong. It was my sister. She put her hands over me and pulled the covers away slowly and one by one. I surely thought that she was going to tickle me to death. She pulled my shirt up to reveal my stomach and I braced for the intense tickling. I was instantly fooled when she grabbed my pyjama pants and lightly tugged on them. I twitched and she instantly stopped.
After a minute or so, she continued and slowly pulled my pants down. She then grasped my boxers and pulled those down too. My penis was already hard because of how horny my sister pulling my pants down made me. I flicked my penis to scare my sister and I saw her jump. She let out a small squeal and then gained back her composure. She then touched my penis with the slightest ease. It felt so good to have her soft nimble fingers touch my penis. She then grabbed my penis with a fist and lightly pumped up and down. This was a sensational feeling that tingled all the way through my body. My stomach was quivering a little bit because of the tingling and there wasn't any clothing covering it.
She suddenly stopped and reached for a bottle. It was obviously some lotion. She squirted some into her hand and started to stroke my penis again. She seemed very good at this because I was getting a lot of satisfaction from her. She did these elaborate hand movements that every once and a while gave me like these little mini-orgasms. She progressively got quicker and went back to the fist. She pumped faster and faster. I thought I was going to have my most intense orgasm ever. I finally reached the climax and ejaculated all on my stomach and some on my shirt. My orgasm lasted for about 15 seconds and was the best 15 second orgasm I've ever had. She left the room and came back with a washcloth in her hand. She wiped my penis and my stomach and pulled my pants up and put my shirt back down.
The next day, I wasn't sure if I should confront her or not.