I was 18 at the time of this story and my sister was 16. I had just finished high school and I was heading for college in the fall. I was 5’ 10” 175 pounds and I was in very good shape from playing sports. My name is Jim and I was also a bit of a nerd. Between studying and sports I hadn’t even started dating yet. My sister Beth was 5’ 5” and a trim 105 pounds with perfectly pointed C cup boobs and a very nice bubble butt. She had silky long natural blonde hair with piercing blue eyes and a very hot mouth. She was a bit shy so she hadn’t started dating yet either. My parents had decided earlier in the year to make Friday night their date night. While they were out we would get something for dinner, play a video or board game together and then get dressed in our bed clothes and watch a movie. Generally I wore shorts and a t-shirt and Beth would wear a pair of pajamas. After a few weeks I noticed that she didn’t wear a bra. This is about the time that I noticed that she had a hot body. It did make me feel weird that I thought that my little sister was hot, but I figured nothing would come of it so it wasn’t a big deal. She started teasing me and did it more and more as time went on. She would have her pajama top undone to the middle of her boobs and lean down in front of me to pick something up giving me a very clear shot of her perfect boobs. She would also bend over in front of me to pick something up while facing away from me and her gorgeous butt would be half-exposed proving that she wasn’t wearing panties. It was always done in somewhat of an innocent way so I couldn’t be sure if it was accidental or not. We watched all kinds of movies together until I discovered that Beth liked r-rated horror movies. I thought horror movies were OK but every time a scary scene came on she would bury her face in my chest and rub her hard nipples across my arm and chest. Every time she did that it caused my cock to get rock hard. She knew that she was doing it to me also because she would look down at it when she thought that I didn’t notice. It was then that I decided to only wear loose shorts and no t-shirt. Although I told her it was because it was getting warmer it really was so that I could feel her nipples rubbing across my chest better. Beth then started wearing short sleeve or no sleeve tops made of much thinner material and loose shorts. She stepped up her teasing game too. Every time there was a scary scene she would run her hand across my hard cock and rest it on my leg right beside my cock while she buried her face in my chest. If she got really scared she would grab my cock and hold it until she relaxed. When she did that I would hold her and kiss the top of her head until she calmed down. When the movie was done we would give each other a hug and kiss and go to bed. My cock would still be hard from all of her teasing and she would rub her body into it and slide her hard nipples across my chest. She would kiss and lick my earlobe each time and whispering goodnight into my ear. I would then kiss my way from her shoulder up to her ear and lick her ear and whisper goodnight to her. She would then smile and walk off to her room to go to sleep. I would go to my room and jerk off to thoughts of her hot body and what I would like to do to it. I found out later that she was doing the same thing. Since I was now obsessing over my sister’s hot body I decided that I needed to step up my game a bit. I picked up a horror movie that was extremely scary and rated X for a very hot sex scene. It featured completely naked men and women. On that Friday we both dressed up and went out to a nice dinner at a place where no one would know us. She wore a low cut short dress that showed off her boobs and her legs very well. It was obvious that she was not wearing a bra. I told her that she really looked hot and that she was going to make all of the other guys jealous of me. She smiled and turned a little red and said “that’s what I was hoping for. I also hope to make all the girls jealous because I am out with such a hot guy.” I smiled and said “thanks!” Once we got home we decided to skip the game and watch the movie. While she was getting a drink I bumped into her shoulder and she said “ouch” I said “aww let me kiss it and make it better” and I kissed her shoulder through her dress. She said “you didn’t hurt my dress you hurt my body so you have to kiss my body”. I took that side of her dress and slid it down her arm until her boob was almost completely exposed. I then planted kisses up her arm, around her shoulder, down her boob as far as it was exposed, and then up her neck to her ear. Her nipples were hard, her breath was getting quicker and she was a little flushed. I whispered in her ear “does it feel better now?” She exhaled and said “wow yes” and she went to her room to get dressed in her nightclothes to watch the movie. I went into my room and changed into my shorts and then setup the movie. When she came out she was wearing a soft fuzzy robe. I looked a little disappointed and she knew it so she walked over and stood between me and the TV and dropped her robe to the floor. She was only wearing a camisole top with spaghetti straps and bikini panties that were both see-through. I just stared at her with my mouth hanging open. She got a very hot look on her face and she licked her lips as she blatantly watched my cock get hard. She then lay down on the sofa and said “would you please massage my back?” so I did. As I massaged her back she kept moaning saying “that feels so good!” while laying there with a blissful look on her face. Her butt looked incredible in her see-through panties and it made me want to rip them off and bury my face in her pussy. Finally I sat down and started the movie. She decided that she wanted to stay lying down and she rested her head on my leg. Her soft silky blond hair felt so good on my legs. I rested my hand on her side and she put one arm behind her and her other hand on top of mine. A scene came on that was a little scary and she squeezed my hand and pulled it up to the bottom of her boob. One of my fingers grazed across her nipple which was hard and I moved it back and forth very slowly. A startling scary scene came up next and she rolled over and screamed and rammed her nose into my cock. I said “ouch. Now you have to kiss it and make it better”. She then got a devilish look on her face and she kissed my cock through my shorts. I said “you didn’t hurt my shorts you hurt my cock so you have to kiss it and make it better” She got a bit of a scared look on her face and she shook her head no. I said “OK now you owe me one” She shivered a little and rolled back over to watch the movie. I put my hand on her side again and she pulled it up to her boob. I went back to slowly playing with her nipple while we watched more of the movie. Another startlingly scary scene came on and the same thing happened. She kissed my cock through my shorts but would not kiss my cock. I told her that now she owes me two and she shivered and rolled over to watch more. Then the scene that I was waiting for happened. A girl and a guy were in a park alone. The girl did a sexy strip tease for the guy and I commented “she has a sexy body although it’s not as nice as yours Beth.” She kissed my hand and put it under her camisole on her naked boob. I alternated between her boobs squeezing and playing with her nipples. Beth moaned as the guy got down on his knees and started licking around her pussy. She then said “that looks so hot!” and moaned and shivered a little. I then had Beth sit up and she gave me an odd look but when I knelt down on the floor and spread her legs she moaned a lot louder. I started at her left knee and kissed my way up to her pussy. I then breathed hot air through her very wet panties over her pussy and then kissed my way down her right leg. She grabbed my head and said “you’re going the wrong way”. I said “there’s a road block” She then took off her camisole top and slid off her panties. She looked so hot totally naked with he butt slid to the edge of the sofa and her legs spread wide to completely expose her shaved pussy. I then started slowly kissed my way towards her pussy but she grabbed my hair and pulled my face against her pussy. I licked around her outer lips and she started shivering and moaning. She was still intently watching the movie as she said “he’s about to make her cum and I will be right along with her”. I then stepped up to a full attack on her clit and within a minute she was screaming in a very intense orgasm. I got up, took off my shorts, sat back down on the couch and she fell back over panting with her head on my leg again. After a minute or so Beth caught her breath and started watching the couple on the screen again. She watched the girl on the screen take off the guy’s shorts. She moaned when his cock popped free and then turned her head and looked at my cock saying “his cock is not nearly as big as yours is”. She then kissed my cock and I moaned but she turned her head and went back to watching the movie. I reached over and started playing with her nipples again. Beth moaned as the girl got down on her knees and put his cock in her mouth. They then showed a close-up view of her licking and sucking his cock. The girl on the screen was really good and they showed it all. Beth’s face was flushed and her breath was very ragged while she watched the hot scene. After a few more minutes the guy on the screen was about to cum so the girl stuck out her tongue and rested his cock on it while he fired his first shot of cum. Then she put his cock back in her mouth to take the rest of his cum and swallow it. Beth moaned and came as the guy was shooting cum into the girl’s mouth. Beth’s breath was just returning to normal when the monster suddenly attacked the couple on the screen. Beth shrieked and spun around to hide her face in my lap. Her open mouth went over my cock at the base of it. Luckily she didn’t clench her teeth; she just slowly closed her lips around my cock. I said “ouch, you need to kiss it and make it better” and she looked up at me and smiled. The head of my cock was wet so she licked the pre-cum off of it and I shivered. She then licked up and down my cock and started playing with my balls. Her tongue felt like hot velvet on my cock and her soft silky hair on my thighs just added to the feeling. She then started licking my cock head and very slowly started working my cock into her mouth. I thought her tongue was hot but her mouth was like a velvet volcano. Her tongue never stopped as she worked her way down my cock, it just kept dancing all over my cock and driving me crazy. I said “Beth you are an incredible cock sucker and you have to know that I am not going to last very long!” She lifted her mouth off of my cock just long enough to say “I hope you don’t last long because I have wanted to taste your cum for years!” I was shocked by her saying that but pure lust took over as she started sucking and licking me again. I would like to say that I lasted a long time but between all of the teasing and her incredible cocksucking I was shooting more cum than I had ever shot in my life into her mouth in about a minute. She backed off my cock so that just the head was in her mouth and she kept swallowing as I kept shooting. Once I was done cumming I passed out. I woke up a few minutes later to her head lying in my lap gently licking my cock and balls. “That was the most incredible thing that has ever happened in my life” I told her. “Thank you” she said “and you gave me the most incredible orgasm that I have ever had also”. We just stayed there for a few minutes caressing each other and enjoying our afterglow when we heard our parent’s car door closing outside. We both jumped up and I stopped the movie and jumped into my shorts while Beth put on her robe and hid her clothes under the couch. When our parents came in they hollered down to us “we brought you two a present so please come up and get it”. I looked at Beth and we both smiled and went upstairs. I already had the best present I could possibly get. If you liked this story I can write more.