Note: This story was dynamically reformatted for online reading convenience. Step-siblings Description: Slater and Jenny are step-siblings, but their relationship gets a lot more intimate. (mf) Slater I rushed downstairs when I heard the door being unlocked. My step-dad always got take-out after my step-sister's martial arts classes and I was really hungry, so when I got to the door I grabbed the food off of him and sprinted to the kitchen to put it on the table. I impatiently waited for the rest of my family to sit down, ripping into my food the second they did. My step-dad was a pretty cool guy, although he was really different from my real dad. My dad was a SEAL, one of the deadliest men in the country, while he was a doctor, somewhat scrawny and really brainy. I wasn't sure why my mom picked someone who was completely the opposite of my dad, but I didn't really mind. My mom was nothing special, as least to me, but I might be biased against her because she's my mom and that's gross, although some of my friends who had come over had told me she was hot. I look nothing like my mom, taking after my dad entirely. I was 6" even and still growing, heavily muscled from my hard workout regime with grey eyes and black hair I kept in a military buzz cut. Jenny, my stepsister, was really hot, around 5'5', with long golden hair and an all over tan. She was pretty toned from her martial arts and cardio workouts, with a small, tight ass and around 34C tits, although I had never actually seen her bra so I wasn't sure about her breast size. I was really glad we didn't share a room, because it would have been really awkward. Our family was fairly well off, with a doctor and a lawyer as the sources of income, so we lived in a decent sized house with an inground pool and hot tub. I woke up the next morning and went downstairs to do my workout, going for around 10 minutes before I was joined by Jenny. We worked out in silence, me lifting weights and her running on her treadmill. I was finished before her and went upstairs to shower. Jenny As he walked up the stairs, I let out a sigh of relief. Slater was an absolute hunk, the target of my fantasies for quite awhile, and looking at his muscles rippling while he lifted was hard to ignore. I finished the last of my run and turned off the machine, heading towards the shower. I got into the shower, quickly cleaning off before I started to think of Slater, my nipples hardening and my pussy starting to get wet. I quickly rubbed my self to an orgasm, not wanting to be distracted during school. After breakfast, we both got in Slater's car. Although we were both 17, Slater was born earlier in the year, so he got his license first and had been driving us both. I sat quietly in the car, feeling awkward being beside the person I just masturbated to, but the ride passed without incident and I got into the school, forgetting about the morning as I focused on my work. After school, I started walking to Slater's car when one of the boys from my second period class came up to me. "Hey Jenny, I was wondering if you want to go out sometime?" He asked. I wasn't even sure what his name was, let alone being interested in him, so I told him "No, but thanks anyways." "Aw come on, why not?" He whined. "I'm not interested." I replied, brushing him off and starting to walk away. He grabbed me, saying "Come on, give me a chance." He was starting to make a scene, with a couple people gathering around. I let out a sigh of relief as I saw Slater come out the door with some of his track & field buddies. Slater jogged over. "What the hell's going on here?" He asked. "This guy won't leave me alone." I responded. The guy who was bugging me now had his eyes practically popping out of his head, staring up at the wall of muscle that was Slater. "I think you should leave." Slater growled at him, sending the guy running. "Come on, let's go." He said turning to me. We got in the car and started to drive when he asked me what happened. I explained to him, getting a nod at the end of the story. The rest of the week was pretty much normal, although I noticed significantly less guys checking me out when they thought I wasn't looking. Slater I was worried that Jenny might get bothered again, but everything turned out alright. On friday, she went to martial arts as usual, but when she got got back, she had a massive grin on her face. As we ate I casually asked "What's the big smile for?" "I got my next belt." She replied, still beaming. "That's cool," I said "need someone to practice with?" She looked at me skeptically, asking "What do you know about martial arts?" "You'll have to try me and see." I said, winking at her. I woke up the next morning, went downstairs and to my surprise, she was already down there waiting for me, a little ring set up. "Anxious to be beaten, are we?" I taunted. "You may be strong, but you don't know anything about martial arts. There's no way you'll beat me." She said. "Wanna bet?" I said. "Bet what?" She asked. "First to 4 wins gets the other one to do anything he or she asks" I said. "Deal." We shook on it, taking our stances Jenny I was a little worried about Slater being confident enough to bet, but I figured my skills would beat his strength in the end. I started circling, searching for an opening. His leg was out, so I leaped at it, hoping to get it in a leg submission hold, but as I leaped he did a spin, avoiding my leap and kicking me in the ass as I passed, leaving me flat on the ground on my stomach. "Oh." I said, both out of surprise and from the electric feeling I got where Slater had touched me. The pleasantness of Slater's touch soon turned to agony as he stepped on the back of my knee and grabbed my foot, twisting it cruelly. I tapped on the ground desperately, in far too much pain to try and get out of the hold. "Where did you learn that?" I asked. He laughed and replied "My dad was a SEAL, these are the combat techniques he used, which he taught me." I realized then how little of a chance I had, with his SEAL combat and strength against my intermediate martial arts. "Well, I may as well give up then." I pouted. "No, we're still gonna do this." He said, picking me up and placing me on my feet. The next two rounds passed just as fast and i was really frustrated, so I cheated, throwing a side kick at his chest. He caught my foot, knocked it to the side and grabbed my nipples, twisting them different directions and pushing me onto the ground. I let out a gasp, more from pleasure than pain, as my body became putty under his hands. He held me like that, counting to three before getting off and saying "I hope you're ready to work hard Jenny." With a giant grin on his face, he turned and started walking up the stairs. I groaned, realizing that the rest of my march break would consist of being ordered around. Slater I chuckled, thinking about how I had duped Jenny. At best, I was hoping to feel her up a bit, but when I got her to bet, it got even better. On top of getting a nice feel of her ass, I had pretty much confirmed that Jenny thought I was attractive as well by turning into butter with the nipple twist. I knew by the look of bliss in her eyes when I grabbed her tits that she would be mine by the end of the week. I woke up really early, excited and wanting to make Jenny feel the oppression she would be facing the rest of the week. I marched into her room, clapping and yelling. "What the hell?" She asked groggily. "It's fucking 5 in the morning." "Seems like a good time to make me breakfast, don't you think?" I said jumping around with energy. She groaned loudly but started to get ready, so I cleared out and went to sit at the table. She came down around ten minutes later and started to cook. I strategized on how I would do this, glad my parents had left last night to go on their vacation, as it would give me more space to maneuver. As she was cooking, I came up behind her and ran my fingers gently down her spine, feeling her shudder as I did so. "Almost done?" I asked. She seemed distracted, but responded that it would be ready in around 5 minutes. After eating, I got her to do my laundry while I went downstairs to workout, coming back up a half hour later to see her eating breakfast. I walked up behind her and gently breathed on the back of her neck, brushing my fingers against her shoulder. The rest of the day went pretty much the same way, her doing minor chores and me giving her the occasional little touch with my fingertips. I liked my progress so far, as she seemed to try to push herself into my fingers by the end of the day. I woke up at my normal time today, deciding that I would give Jenny an easy day since most of my chores were done anyways. I went downstairs and made my own breakfast, having enough time to finish and put away my dishes before Jenny came down, looking confused. I told her that I was giving her an easier day today and she started smiling. I just shrugged and went to sit on the couch, planning to order a movie. I smiled inwardly when she sat down closer to me than she usually does and asked "Anything you want to watch?" She suggested a movie and I turned it on. The movie was actually pretty good, although it had a bunch of typical overused horror movie scenes. I was surprised that Jenny had picked a horror movie, as she scares easily, but I took full advantage and soon had her sitting beside me, rubbing her back and hugging her whenever she freaked out. By the end of the movie, I was barely paying attention to what was on the screen, focusing on caressing her entire body except for sensitive spots. As soon as the movie was over I excused myself, knocking her off balance because she had been pushing her body into mine as hard as she could. I was beaming on the inside, although I thought I hid it well, surprised at how fast I was making progress. We watched another movie, this time her resting against me the entire time before I left for a friends house for the rest of the day. I came back around 11 that night, a little drunk and really high, hoping to just sneak into the house, when I heard Jenny yell my name and come running down the stairs. "Oh shit!" I thought to myself, completely forgetting the bet and what I was trying to accomplish that week. She appeared at the bottom of the stairs in her pajamas, her nipples clearly poking out. "Hey, Jen." I said, wincing at the slur in my voice. "Slater! I missed you." She said, running over and giving me a hug. I just about fell over, as my balance wasn't too god at that point, wondering why Jenny was hugging me. It all rushed back at once and I realized what was happening, bringing a smile to my face. "It's nice to see you too, Jenny." I said, rubbing her back. I decided to test my luck and reached down to grab her ass cheek, drawing a gasp and her nipples poking me even more than they already had. I gently massaged her ass for about ten seconds before breaking the hug and telling her good night, walking up to my room. The next day I was slightly burnt and hungover so Jenny was once again doing things for me all day, although I tested my boundaries a couple of times, grabbing her ass and tits, which always made her press her body against mine, gasping or moaning in pleasure. I woke up for the fourth this time that week, now back to 100% and ready to start making the final move. I went downstairs to see Jenny eagerly waiting for me, rushing to give me a hug as I reached the bottom of the stairs. I pulled her in, massaging her ass for a little before pulling back and planting a little kiss on her lips. I paused to judge her reaction, but was interrupted by her kissing me back, much more aggressively than I had, our tongues intertwining. I lifted her and carried her to the couch without breaking the kiss, running my hands from her ass up to her nipples, gently twisting and pinching them. She moaned in my mouth, thrusting her chest towards me. I broke out of the kiss, then started to take off her shirt, not entirely surprised she wasn't wearing a bra. I kissed her cheek, where her neck and chin meet, the base of her neck, the hollow in her shoulder, the top of her right breast and then finally took her nipple in y mouth, suckking gently as I moved my tongue in circles around it. Her skin was now a deep pink, as though she had a sunburn, and she was holding my head against her, moaning and gasping. I switched nipples every once in awhile, finally planting three kisses on her belly button before giving her a list of chores and saying "That's all you get for now." She looked at me desperately, her eyes full of lust and disappointment, as I put her shirt back on, picked her up and gave her a smack on the ass to get her started. She walked away to go do the work, shooting me a loom over her shoulder as she did. Eventually she finished the work, coming to sit with me on the couch, but I pushed her away, wanting her to need me, for me to be the only thing on her mind. My plan was now pretty much finished, as I was sure that she would practically jump me tomorrow when I woke up. I woke up the next day, full of energy as I thought about what was going to happen. I came down the stairs, and, as expected, Jenny was waiting for me at the bottom. I walked slowly down the stairs, brushing past her and ignoring the hug. I sat down at the table and told her to cook, almost laughing at the look she gave me. All through the morning, I pushed her away when she tried to get close to me, giving her little gropes when she had given up, then quickly walking away. We went on like this for around half the day before she broke down. "Please." She whined after I gave her another grope. "Please what?" I asked grinning at her. "Please..." She looked at me, and I knew I had broken her to my will. "Beg me for it. Tell me what you want." I ordered. "Slater, please fuck me, I need you right now." "Good girl." I said, sweeping her up in a hug and kissing her. She pressed against my body, her nipples fully erect, clinging on as if it was life or death. I massaged her ass cheeks as I lifted her and brought her upstairs, quickly disrobing both of us before tackling her onto the bed. I moved my mouth down to her nipples, quickly sucking them both before planting a kiss on her belly button and stopping just above her pussy, which was now dripping wet. I inhaled her aroma, savoring it before plunging a finger in and finding her g-spot, rubbing it furiously while sucking hard on her clit. She was bucking wildly, holding my face to her and screaming my name as I brought her to orgasm. I moved up, kissing her with her juices still on my lips and brought my dick to her pussy entrance and turning her over into doggy style. "You've got an amazing ass." I told her as I thrust in with one stroke, her pussy juices plenty enough lube. She gasped with each thrust as I hilted over and over, feeling the tip of my dick hit her cervix with each thrust. "Oh, fuck yes Slater, give it to me hard." She moaned before I felt her pussy walls clamping down on me and her body start thrashing around as she screamed out my name. I kept pumping, the feel of the muscles in her wall trying to milk me increasing my pleasure, driving me to my own orgasm. "Oh fuck, I'm cumming." I yelled. "Cum inside me she moaned. Fill me up with your cum." I obliged, knowing that she was somewhat sexually active and on the pill. I thrust as deep as I could, spraying my cum all over her cervix in 6 long bursts, staying inside her as my dick slowly softened. "Slater, that was amazing." She said as I flopped over sideways onto my back, completely spent. She turned over and lay down with her head on my chest, both of us just laying there, enjoying the feeling. "You're mine now, I hope you know that." I said. "Always. " She responded. Jonathan I was sitting at the kitchen table, waiting for breakfast, but mommy wasn't awake yet. "Daddy, will you make me breakfast?" I asked. "One sec, I'll get your mother he responded." Mommy came out a little after he went into her room. Mommy was always smiling when daddy was home, and really sad when he wasn't. For some reason, she does anything he says. At first I thought it was because daddy was the guy, but my sister refused to do anything for me, so that wasn't it. I asked him "Why does mommy do what you ask but Emma doesn't do what I ask?" "Well, it all started with take-out...