My sister and I have always been very close and affectionate with each other. So much, in fact, that when we went places together people often thought we were dating. But it never went further than a hug or a kiss on the cheek. I’m 22 now, she’s 18 and still lives at home, so, since my apartment has an extra bedroom which I don’t use, she often visits and spends the night. I even let her have parties in my place when I’m away and occasionally even when I’m in town I’ll tolerate a soirée. But a funny thing happened one night and it opened up a whole can of worms that I'm a little reluctant to talk about. But, as long as you don't go spreading it all over town, I'd like to share what happened. I think I can trust you not to judge me, can't I? Well one night Jennifer—that's my sister—she was having a sleep over with some of her closest friends from college and the girls were getting a little wild. I have a large office/study with some gym equipment set up in the corner and I had been working out. I got up to go to the kitchen for a protein drink and when I opened the door I was shocked to see my sister and the four other girls, Beth, Neesha, Candy, and Kylynn sitting around the kitchen table in various stages of undress, playing strip poker. Neesha, a very cute, slightly plump little thing with large breasts, shoulder-length straightened black hair and a ghetto booty, apparently was not very good at poker because she was not wearing a stitch of clothing. I mean not a damn thing. So when I came out the first thing I saw was her bulbous brown ass perched up on top of a barstool with her backside to me. Next to her was Candy, a tiny little asian chick and she obviously wasn't much better at cards because she was in a thong and a pair of patent leather shoes with white knee high socks. She was the only one who attempted to cover her breasts when I came out but when she saw the others didn’t care she stopped caring too. My sister, whom I’ve seen naked by accident getting in and out of the shower once or twice, was only topless and apparently winning because Kylynn was wearing only a bra, Probably because she has the smallest tits of the five, but Incredible long muscular legs and a killer-tomato ass. Beth was in her panties and socks but naturally she had her enormous boobs on display—They’ve gotta be G’s or something and she's always been quite proud of them. I tried to play it off real cool like it didn’t even phase me but I was phased all right. I'd known these girls since junior high and never even thought twice about them in a sexual way, obviously, but now that they were of age, seeing them like that was a very...well, it was an interesting experience. They'd certainly blossomed. I got my drink and was about to go back into my office when Neesha lost another hand and was out of the game. She jumped down off her barstool so she was blocking my path and did a little defeat dance. “So now what am I gonna do?” Neesha asked. “Go chill with my brother,” Jennifer said, “He won’t mind the company.” “Can I have my clothes back then?” “Hell no, you lost ‘em. You gotta walk around like the naked loser you is, girl,” said Kylynn. Neesha turned to me, shrugged and grabbed my hand, leading me back to my study. “You don’t mind if I hang out with you in the nude do you? hee hee!” she said. “Oh I guess it’s okay just be gentle with me, I’m a virgin,” I said. I felt funny about being alone with one of my sisters friends like that. I mean she was totally naked and just acting perfectly casual about it but now that I think of it, she was digging it. I guess the girls felt safe with me because I had always been very neutral and never showed any interest in any of them. Plus I was the brother of their friend so they knew I was safe—I’m sure Jen spoke very highly of me to them. They could practice flirting with me with no repercussions and I got the impression they were making it kind of a challenge to see who could make me crack and lose my cool. So my job was to keep myself under control, but Neesha looked so fucking hot and kept rubbing up against me. Y’know that thing girls do, like, in the office when you’re working with them, they stand next to you with one breast kinda poking you in the arm or in the side. Sometimes its just one nipple barely grazing you but they act like they don’t notice it but it’s totally dominating your thoughts. And you’ve gotta concentrate and act like you don’t notice it either. God, that drives me nuts, and now Neesha was doing it but with her bare breasts on my bare arm. Jeezus and her nipples were getting hard too. So I was showing her the exercise equipment and when I demonstrated the pec-deck she put her hands on my pecs so she could feel them flex. Then when she tried it, she insisted I have my hands on her “pecs” and she has these really perky high riding tits and every time she flexed they would jump up and touch the palms of my hands. I started bulging in my pants but they were tight jeans so I didn’t make a tent but I definitely had a salami growing down my leg. She spotted it of course and ran her hand along the length of it. “Ooh, so you ARE glad to see me,” she said. I just chuckled and ignored it, but it was getting pretty hot in there. Then we hit the bench press and I don’t know what I was thinking, I guess I was just showing off 'cause I normally bench 235 to 250 at the most, but this time I loaded up the bar to 275! I told Neesha to stand behind the bar and spot me. I was concentrating on moving the weight but she had her snatch right above me and her legs apart. I got the bar off the rack and lowered it to my chest and in my peripheral vision I noticed she was really wet down there and it distracted me so when I went to push the bar back up ... I couldn’t! I told Neesha I needed help so she moved in to grab the bar and straddled my head! And when she bent her knees to lift the bar, suddenly my face was buried in her sopping wet koochie and my nose was poking her asshole! Needless to say I did not make a very good effort at lifting the bar and she couldn’t lift it all by herself so all her weight and some of the bar’s weight was bearing down on my face and shoving it farther into her snatch. I couldn’t say a word to get our lift synchronized nor could I get a deep breath for the effort. She didn’t know what to do and was either stunned or liking it too much to move. So I thought of a way get her attention. I had this rapid fire tongue technique that I’d used on girls before and it was always way too intense for younger girls because their clits are more sensitive. So I start batting her clit around with my tongue like a boxer on a speed bag: “back-it-a-back-it-a-back-it-a.” She jumped up and left the bar on my chest, which was okay, but you should have seen the look on her face. Like she’d just had her first taste of the Ambrosia of the Gods. “What the hell did you just do?” she said. “I had to get you off of me; I couldn’t breath! Sorry!” I said with a smile. “Oh my god! Kurt that was incredible! I’ve never had a guy do anything close to that. About 3 more seconds and I would have come all over your face!” she said. “Oh you liked it? Usually the young ones can’t take it.” I said as we synchronized lifting the barbell off of my chest. “Well It was so intense I almost couldn’t but, well, I kinda masturbate a lot so my clit is used to a lot of abuse. You gotta show me that again! Please?” “Oh no! You tricked me into that, I don’t think we should go any further with this...” I said. “Oh Ple-e-ese Kurt, you just gotta! C’mon, c’mon Kurt, be my sex-ed teacher, you have experience and I’ll be a good student I promise. Please do the wap-a-da-pa-da-pa thing on my clit again!” “The wap-a-da-pa-da-pa thing eh? You’ve already got a name for it?” “Hee-hee, well yeah, that’s what it’s called: ‘Professor Kurt’s wap-a-da-pa-da-pa thing!’ Hahaha! didn’t you know that? Tee-hee. Neesha laughed, and she was being so cute, I cracked. I had her sit on the pec-deck and I lowered the hand grips so she could hang her legs over them which put her in a completely spread open position. She looked so sexy and I could tell she was digging the hell out of it. She had that breathless half smile and that sultry, smouldering look in her eyes as I knelt in front of her and ran my fingers down her inner thighs and gently parted her lips. Then I described what I was going to do to her in great detail in a very clinical tone. She was beside herself with excitement and started giggling uncontrollably. “Okay Neesha my dear, first we’re going to get you nice and warmed up with some long tongue strokes straight up from your butt hole to your naval but were not going to penetrate the vagina just yet. So we’ll use a wide flat tongue as we contact the Labia majora and clit, pressing just hard enough to lift the hood of the clit slightly. Then I’m going to pull the hood up a little higher with my upper lip while I make little clockwise circles with my tongue around your clitoris...” “Okay, okay hee hee, just do it! I can’t stand waiting any longer! haha Hurry!” she begged. As the tip of my tongue touched her asshole, and went in a litter deeper than she expected, she gasped and started moaning. By the time I got around to the wap-a-da-pa-da-pa thing, she was squealing with delight and literally dripping all over my pec-deck seat. Her three second estimation was pretty accurate and the next thing I knew she was thrusting wildly and holding my head with both hands, jamming my face into her pussy. She came hard and didn’t stop coming for about a full minute. When she relaxed and let go of my head, I got up and turned around to see Kylynn standing just inside the door which she had closed behind her. “KYLYNN!” I yelped, “How long have you been standing there?” “Long enough to see that you definitely know your way around the female anatomy,” she said. “Guys my age don’t know a damn thing about eating pussy. I think I’m gonna need a little demonstration too, Kurt.” “Now wait a minute, it’s bad enough I did this. I can’t just start...” “Yes that was very bad of you Kurtiss, your sister would be shocked. But she doesn’t have to know If you agree to my terms. But just so you know, Kurtiss, this is not a date or anything like that. You’ll simply be providing a service. I’ll be like a student and you’ll be my private tutor,” explained Kylynn. “That’s funny, Neesha said almost the same thing. Except she didn’t blackmail me,” I said. “Well I AM blackmailing you,” said Kylynn. Then she laughed, walked over to me and dropped her sweatpants to her ankles revealing the cutest little shaved camel toe and said, “C’mon Kurt, you know you’ll enjoy it.” I was starting to feel like Humpty Dumpty. Next thing I knew I had her on the pec-deck and I’m munching on her delicious twat. But trying to remain calm and resist the temptation to stand up and pull out my crank on her. I remembered the door was unlocked and that my sister could walk in any minute although she’s always very respectful of my privacy and wouldn’t walk in on me without knocking. So instead of locking the door and playing it safe I left it unlocked. I realized later that I was secretly hoping she would walk in and see me in action with her friends. Then my mind started to wander and I found myself picturing my sister on the pec-deck! I had the startling realization that I was getting extremely turned on by the idea of it. Would it really be so wrong if I just tutored her as well just like i’d done with these two girls. I was deep in fantasy when I heard a noise that made all three of us jump! A knock on the door! No one said a word ... then it slowly started to open ... But you probably aren’t interested in what happened next. On the off chance that you are just give me an awesome vote and let me know in a comment and I think something can be arranged. Thanks for reading. I gotta go use my right hand for something else now.