###Jenny By TDB, writing_hard@yahoo.co.uk Danny's younger sister discovers the joys of working out... "Happy Seventeenth Birthday!" cheered Danny's parents as they swung open the basement door. Behind them Danny's 13-year old sister, Jenny, bounced excitedly up and down, clapping her hands. Danny stepped forward and pulled off the blindfold, a big smile lighting up his face as he got his first glimpse of all the shiny new gym equipment now arranged around the room, the walls clad in full-length mirrors, a laden weight rack to his left. His father rested a hand on Danny's shoulder, "You've been pestering us for ages, and as you're trying to get on the track and field team now, we feel that this could really benefit you. But you'd better make frequent use of it mind, we haven't shelled out all this money for a nine-day wonder!" "Don't worry Dad, as soon as school breaks up for summer at the end of the week, I'll start working out daily!" said Danny, imagining as he spoke how impressed all the girls at school would be with his new physique. True to his word, come Monday morning at 7am, Danny made his way downstairs to the basement. For a 17-year old, he was rather skinny - in keeping with his father's side of the family. His mother was slightly more well-built, but Danny seemed to have inherited his father's genes. As he surveyed all the gleaming apparatus Danny became aware of someone else coming down the stairs. In the mirrored walls he saw his younger sister pop her head into the room. "Hey Danny!" she chirped, as he turned to stare at her. She advanced further into the room and Danny saw that she was wearing a tiny little pair of pink lycra shorts and a matching sports top - not a bra, as she was too young to have started developing breasts yet. Her skinny 5' 0" figure hardly filled out her choice of clothes at all - in fact, they hung off her. "Hi Jen! What do you want?" asked Danny, already anticipating the answer. His little sister had always worshipped him and was forever copying him too. "I couldn't ... work out with you, could I?" asked Jenny anxiously. Danny chuckled, "Want to pump some iron, do you?" Jenny nodded eagerly. He thought to himself for a while, his little sister would no doubt get bored with exercising with him soon, and there was no harm in letting her join in in the meanwhile. Maybe she could even spot for him. "Okay Jen. Just copy me, and no fooling around, OK?" Jenny nodded eagerly again. "And you might want to start wearing some sweats down here, " he warned, eyeing her attire, "It can get pretty cold in the basement." Despite Danny's promises to the contrary, by the end of the month his sessions in the gym were becoming more and more infrequent. He had grown disillusioned with his complete lack of progress - something that was entirely his own fault. Like many a teenage boy before him, Danny had opted to begin by lifting the heaviest weights he could, completely sacrificing form as he exercised. Also, although he would never have admitted it, he was slightly embarrassed by the progress being made by his little sister. Jenny had started off curling the lightest weights available - the 2 lb dumbbells - but, joining her brother in the gym every day, by the end of the first week she was comfortable doing sets with the 10 lb dumbbells. Danny had begun with the 20 lbs, and could only manage to squeeze out a couple of reps even whilst leaning back and swinging his arms to gain momentum. It was a similar story with all the other lifts too - Danny made no progress and then had to spot his sister whilst she lifted weights that, after starting relatively light, got slightly heavier by the day. Even the protein drinks, of which he had bought a stack at great expense, had failed to help him increase his lifts or gain even a little muscle. Fed up, Danny had stopped paying daily visits to his basement, and he was only heading down there now - his first visit in a fortnight - to stop his father moaning at him. When he made his entrance he was slightly surprised to find his younger sister already down there. He knew that she had been keeping up her workout routine, it was something his parents pointed out to him when they bemoaned his laziness, but he had been watching TV in the lounge for a good couple of hours and the door down to the basement had been directly in his line of sight, and had remained closed all the time he had been there. This meant that Jenny had to have been down there for over two hours. She stood over in the corner with her back to him, apparently concentrating very hard on her dumbbell curls, with her walkman on and her headphones in. She obviously hadn't noticed him and so Danny, in a very sulky mood, trudged wordlessly over to the weight rack. Rather than do the sensible thing and select a light weight to begin with, he decided to be stupid and looked to pick up the 40 lb dumbbells. Except that when he bent down to their usual position on the rack they weren't there. "Why's that stupid little bitch mucked things up?" was Danny's instant thought. He wheeled round to accost his little sister and, to his great annoyance, saw two empty protein shakes lying on the floor, that Jenny had obviously drained. Danny's temper had been simmering but now it flared and with a red face he stormed up behind his sister, shouting "What do you think you're playing at? You've hidden my weights and now you're drinking my shakes! They're damn expensive, you know!" Jenny, unaware that anyone else had been in the room, dropped the weights she was lifting and wheeled around looking shocked, pulling her headphones out of her ears as she did so. Danny didn't notice the sudden loud hissing of pop music however, he had eyes only for the dumbbell that had rolled to a stop at his feet. The printed letters on the side read: '40 LB'. "Wha ... ?" Danny's mouth fell open. He blinked. He read it again - still '40 LB'. "Wha ... ?" "I'm sorry, Danny," a worried-looking Jenny said, "I didn't think you wanted them anymore - it's been so long since I've seen you down here." Danny backed away, raising his finger to point at the dumbbell, still mouthing wordlessly. Jenny stood there, wringing her hands, looking rather like a rabbit caught in the headlights. Danny looked from Jenny to the dumbbell and then back at his sister, suddenly gaining confidence as he realised how scared she looked. His mind raced - 'it had to be some kind of joke, a trick played by his sister - yes, that was it. But why would she do such a thing? Did she know how jealous he was of her gains? She must be. This must have been a stunt to make him feel bad.' "You lying little bitch!" Danny roared, "Well, I've found you out now, haven't I? And I'm gonna make you pay for this!" He lunged for his sister, who stepped backwards and tripped over the other dumbbell, falling to the floor. Danny leapt on top of Jenny and grabbed her wrists, as she squealed and looked terrified. "Who's laughing now?" Danny spat, letting go of one of Jenny's wrists to slap her round the face. He raised his hand and brought it down with all the force he could muster, only to find it abruptly stopped mere millimetres from Jenny's face. Amazed, he glanced up to see what had halted his arm and found that with her free hand, his little sister had now seized him by the wrist! Danny tried to pull free but to his shock found that he could not budge an inch. Alarmed, he darted a glance at Jenny's face and saw a sudden fire burn in her eyes. Before he knew what was happening, his younger sister had somehow rolled him over and now held him pinned to the floor. Again he struggled, and again he found that he may as well have been clamped in a vice, so strong was Jenny's grip. The look of fear on her face now melted away as her eyes glinted and a hint of a smile played on her lips. "Try to hit your little baby sister, would you?" Her lips twitched again. "Try to hit a weak little girl?" Danny squirmed. "Well it looks like this weak little girl is going to have to teach you a lesson!" Jenny stood up, as she did so hauling Danny to his feet as easy as if he were a rag doll. Try as he might, Danny could not work free - in fact, Jenny's grip seemed to have got even tighter. The young girl climbed onto an exercise step and lifted her elder brother's hands above his head. To Danny's amazement she didn't stop there. Within seconds he founds his legs dangling as he tried and failed to get any purchase on the floor. Jenny rose onto her toes until she could stretch no more and gave a little girlish giggle as Danny's attempts to re-find the floor left him helplessly swinging to and fro. "Sorry to leave you hanging around, big brother!" laughed Jenny "I should really do something about that, don't you think so?" and with that she flung Danny aside. He cartwheeled through the air before connecting with the wall with a crunch that felt like it had shaken his teeth loose. He slid in a dazed heap to the floor, but before he had time to gather his senses, Jenny had hoisted him over her shoulder and was carrying him towards the bench. "In fact, big brother, you're just in time to help me finish my warm-up!" Danny recalled the 40 lb dumbbells, "Warm-up?!" Next thing he knew, he was being held aloft, parallel with the ground, and was being bench-pressed with obvious ease by his baby sister - once ... twice ... three times ... until he had lost count. All the while Jenny wore a look of determination on her face and her breathing remained shallow - this was easy for her. Danny was terrified at the thought of how much she could lift when she really put her back into it. After what seemed an age Jenny lowered Danny gently to the floor, and left him propped up with his back against the bench and his head collapsed into his chest. He was eventually able to groggily look up and saw that his younger sister had cleared a large space a few feet in front of him, into which she now strutted. She smiled ... "Get ready for a surprise, big brother!" Slowly, Jenny began to remove the sweats that Danny had recommended she wear. It was only as she struggled to pull them off that Danny noticed how snugly they now fit her. 'Could it be ... ? Surely not!' Sadly for Danny, he was about to be proved wrong ... A final tug saw the sweats removed and Danny was left looking at his little sister in the same tiny little loose-fitting pair of pink lycra shorts and matching sports top that she had been wearing when she first asked if she could join his workouts. Except they were no longer loose fitting. And his little sister was no longer his little sister...Jenny stood proudly in front of him, bouncing slightly on her toes and giggling as Danny slowly registered what he was seeing ... Every time his sister bounced, it caused her 17 inch diamond-shaped calves, already as pronounced as if she were wearing a pair of 6-inch heels, to bulge even further until they looked sharp enough to cut through steel. Similarly, Jenny's thighs were lean, rippling sinew, each at least 25 inches around. Those pink lycra shorts were no longer baggy, but they did look smaller than ever - they clung to the young girl's legs like they were a second skin, and were seemingly stretched to bursting point. A quick twirl from Jenny allowed her astonished elder brother a sight of her glutes - two perfectly-rounded half-globes of rock-solid muscle, which threatened to rip through the seams of her shorts. Despite her youthful age, Jenny's hips had taken on a womanly flare, which tapered down to a tiny waist. Looking up from this Danny got a glimpse of his 13-year old sister's taught midriff, over which she could have done her washing if she so wished, so defined were her abs - six perfect bricks of muscle. Continuing his astonished eyes' odyssey up his little sister's body, Danny couldn't help but marvel at the glorious V-shape formed by her finely-honed torso. Jenny pretended to blush when she noticed Danny's eyes lingering on her chest, but he didn't care - he was mesmerised. "How in the name of all that is holy did I miss that?" Danny wondered. As well as he could given the circumstances, he tried to recall every time that he had seen his sister in the last couple of weeks. Only now did he attach any significance to the fact that whenever he had - only briefly, it must be said - seen her recently, she had been wearing unflattering, baggy tops at all times. Had she not, she would most likely have given their parents heart attacks ... Her pectorals were now two rippling slabs of muscle, which alone gave her a most impressive cleavage, but Jenny's astonishing transformation did not end there, oh no! Just four short weeks ago Jenny had been as flat-chested as any typical 13-year old girl, but now she had blossomed ... bloomed ... and was blessed with a pair of breasts that would easily fill a C-cup bra - not that she would ever need a bra, such support was given by her awesome pectorals. Her muscle-pumped breasts were as pert, ripe and full as the best Danny had ever had the privilege of laying eyes on. Each nipple was as hard and as large as a bullet, and they seemed to grow before Danny's eyes - Jenny, apparently, was finding herself excited by her little routine and her brother's amazement - until they seemed ready to pierce the fabric. Jenny kept up the blushing routine as she 'accidentally' tensed each pectoral in turn, causing her breasts to dance up and down ... up and down ... up and down. Her lycra sports top, already struggling to contain not just her newly-bountiful chest but also broad shoulders capped with peaks of muscle and a back that was rippling so much that it looked like it had a life of its own, started to rip. Or was that tearing sound her shorts? Both items of clothing looked so ready to give way that it was hard to tell which had inevitably lost the battle first, and it was impossible to rule out the idea that they were both about to burst helplessly open, so muscle-inflated was each of the bodily regions whose modesty they, the clothes were trying to preserve. Finally, Danny managed to tear his eyes away from Jenny's chest, only to discover that there was still more yet to come. Jenny's arms now hung down by her sides, and yet even with her muscles relaxed, they looked as big, if not bigger, than Danny's own pipe-cleaners - even when he flexed them. Jenny flexed her own arms now, and as each bicep got bigger and bigger, Danny's mouth dropped lower and lower - so by the time they had reached their bulging peaks, you could have parked a truck in Danny's mouth! Danny simply could believe what he was seeing - here, in front of him, stood Jenny, his little sister, only a 13-year old girl, and yet her biceps were easily each 16.5 inches round. Jenny straightened her arms and smiled as there appeared an enormous horseshoe-shaped bulge in each ... the amount of meat in her triceps took Danny's breath away - and the definition in her forearms was incredible. Jenny began to repeatedly flex and then straighten her arms until her muscles were so engorged with blood that her arms had grown by what looked like yet another inch and her biceps and triceps bulged so enormously that they looked like they were ready to explode. The occasional vein snaked beneath the skin, supplying her girl-muscle with the fuel it required. Danny looked his sister up and down once again, and was only now struck by her increase in height - it wasn't as incredible as her muscular growth - but she did appear to have shot up a couple of inches from 5' 0" to 5' 2" or 5' 3". He hadn't noticed it initially as there had been quite a lot to take in, but now he could appreciate it he was impressed by the difference it made to her perfectly-proportioned physique. Still, inch-for-inch, Jenny remained undoubtedly the most muscular girl, most probably woman, and possibly even human being on the planet! The only conspicuous fat on her body remained on her face - her skin was still perfectly soft, smooth and unblemished (save a few freckles), just like the rest of her flawless body - but she wasn't podgy; no, rather her face was oh-so-slightly rounded, with plump red lips, a cute little nose and sparkling blue eyes, all of which was perfectly framed with soft blonde hair, tied into pigtails which just tickled the tops of her delts. "And now, big brother, for bullying your poor, weak, little sister earlier, you will receive the punishment you deserve!" Danny felt a shiver run down his spine. He briefly considered running until he realised that he was simply too terrified to move - the thought of what his baby sister's muscles were capable of doing to him left him temporarily paralysed. He remembered the ease with which she had lifted him earlier - not only had her muscles grown enormous, but her strength seemed to have increased exponentially as well. Jenny gave a wicked grin, "First however, I need to prepare ... " 'Prepare? What did she mean?' Danny's panic intensified. "Fact is big brother ... " She made the words sound mocking, " ... I'm still not sure what these little muscles can do." Jenny flexed her teenage biceps and gave them each a kiss, before addressing them, "Come on my little babies, it's time to grow! I need you to grow big for my brother!" Jenny moved over to the stack of protein shakes and proceeded to drain five of them, one after another. Then she strode to the weight rack and loaded up a barbell with so many plates that Danny soon lost count - all he knew was that it resembled the kind of weight that Super Heavyweights clean and jerk at the Olympics. With a deep breath, Jenny hoisted up the weight and began to curl it, biceps straining with the effort, more puffy veins appearing in her arms. Danny could not believe the way her biceps were getting even more muscle-pumped and muscle-petrified with every rep. After what seemed an age Jenny dropped the barbell and moved on to leg extensions. Her quads trembled every time she heaved up the massive weight, and soon began to balloon with seemingly more and more feminine muscle. And so it continued, Jenny pushing herself to the maximum with every exercise, breaking every strength record ever set by even the most powerful of men. Glistening with sweat, her every rep made her girl-muscles grow harder and harder until she stopped and stood once more in front of Danny, who remained still, slumped against the bench. Jenny began to hit some eye-boggling poses, highlighting every single last muscle on her young body to perfection. She culminated with a full-body flex, held it and commanded Danny, "Look at me, big brother, look at me now!" As Danny stared, open-mouthed, loud tearing noises announced Jenny's clothes had finally given up the ghost and, shredded, they fell to the floor. Jenny stood naked in front of Danny, still holding the pose, the most magnificently-muscular animal to ever walk the Earth. Her muscles, which had looked enormous before, had all become so permanently power-pumped that they had all grown by inches. What's more, Jenny's recent superhuman exertions had left her every muscle incredibly defined and striated , her vascularity enhanced, and her body so muscle-petrified that Danny could well believe that it was bullet-proof. Jenny squealed with pleasure as she ran one hand over her steely bubble-butt and the other across the ridges of her brick-like abs. "Look at me!" She beamed, "I'm enormous! And I feel soooo strong!" Jenny now placed her left hand on her right bicep - even relaxed she couldn't reach all the way around it - and slowly began to flex. Despite trying to resist, the fingers of her left hand were easily spread apart, unable to contain the mountainous peak that slowly but surely erupted beneath them. Jenny squealed again as she tried to squeeze her bicep and failed completely to make any kind of indentation. "I'm so hard! Like steel! And my chest!" She placed her hands on her breasts - now so muscle-inflated that you would struggle to fit them into a DD-cup bra - and massaged them slowly, fingers tripping over her bullet nipples. She moaned orgasmically ... "I'm incredible ... soooo young, yet soooo muscular and soooo strong! I mean, just look at my biceps! Most fully-grown men can only dream of having muscles like these! Even my muscles have muscles!" Now Jenny's voice took on a sexy tone, "And most women can only dream of having breasts like these!" She flexed her pecs and bounced them up and down again. "They're huuuge, but they don't sag like Mum's, and hers are tiny compared to mine! She'll be so jealous when she sees that her 13-year old daughter's breasts have outgrown hers! I must be a DD-cup now at least, and she's only a B-cup! Maybe I should ask to borrow one of her bras, and let her watch me struggle to fit into it! And the girls at school will be surprised when they see me - no one in my class even has tiny boobs yet! Penny may like to strut around in tight sweaters or her leotard, but her padded bra doesn't fool me! I can't wait until she gets a glimpse of these melons when we change for gym class!" Jenny giggled at the thought as her hands continued to fondle her breasts, "Soooo big! And soooo firm and ripe!" She moaned joyously again, before looking down at her legs, "And I can't wait to see these in a pair of high heels either! Not that I need them! I must have the sexiest legs on the planet!" She bounced up and down again and watched her muscles bulge and ripple with glee. "Now I think of it, I'll need some new clothes ... I'll have to try and squeeze into Mum's because there's no way I'll fit into any of my old things!" Suddenly, Jenny turned her attention to Danny, "But first, your punishment!" Danny cringed. "Get up!" she barked and, fearfully, Danny sprung to life. "Come here, you big, big, strong boy!" his little sister whispered huskily. Danny staggered over and collapsed at her feet. Jenny smiled, "For years, Danny, I have worshipped you, but now it is I who am the goddess, I think it is you who should be worshipping me!" Jenny hit a double biceps pose, "Worship me!" she whispered again, and Danny had no choice but to obey ... Head bowed, Danny kissed his little sister's feet, his hands beginning to stroke her calves, fumbling fingers probing the deep ridges of unyielding teenage muscle. Jenny stood still, hands on hips, staring down at the top of her elder brother's head, as she quietly enjoyed her total control over him. Danny was now working his way up Jenny's thighs and was at the same time working himself into a state of blissful muscle-lust. So great was the quantity of muscle to be worshipped that it was taking him a very long time to make any progress. Slowly, Danny moved further and further up his sister's legs, frenziedly caressing and kissing her utterly solid quads but, as he neared the top of Jenny's legs, she seized a handful of his hair and snapped his head back. "Naughty, naughty!" Jenny scolded, "Have you forgotten that I'm your baby sister?" With that Jenny slammed Danny's face into her quad, which might as well have been a brick wall, judging by the way Danny's whole body convulsed in agony. Jenny snapped Danny's head back once again, "Looks like you're getting a little too attached to my thigh muscles, big brother! Perhaps you'd like to see what they can do?" The fear in Danny's eyes said different, but there was nothing he could do as Jenny straddled his back and then slid his neck between her legs. She flexed and her legs came suddenly alive, rippling and bulging with girl-muscle that solidified and trapped Danny's neck, cutting off his air flow. He coughed and spluttered, but Jenny wasn't about to loosen her grip yet, instead she squeezed, revelling in her new-found power. Danny's body was slowly wilting as he flailed his fists a couple of times, managing to punch Jenny's thighs - but the young girl was so rock-solid that she didn't feel a thing, unlike Danny, whose knuckles were now bruised and raw. Jenny moaned as she gave one final flex and then spread her legs, giggling as she watched her brother's limp body hit the floor. Danny's ordeal wasn't over yet though - he recovered consciousness to find his sister lifting him once more, until his head was level with her midriff. Jenny pressed his face into her stomach, which didn't give an inch, and began to rub it up and down her abs, each separate muscle of which felt like a road-bump to Danny. Jenny eventually let go of her big brother for the final time, and laid him tenderly on the bench. His face was swollen, his eyes puffy, his nose red, and his little sister had totally dominated him ... Jenny climbed the basement stairs and cautiously stuck her head out of the door, hoping to conceal her transformation from her parents for a while yet. She need not have worried - she was just in time to see her mother and father pull out of the drive in the car and disappear down the road. With Danny still unconscious in the basement, she now had the run of the house and, naked, skipped happily upstairs to her parents bedroom. It was there that she hoped to find something amongst her mother's clothes to fit her awesomely-muscled young body. She began by rifling through the underwear drawer and soon found a lacy black thong. Jenny had never worn a G-string before and decided to give it a try - she carefully eased the sexy pair of panties up her well-developed legs and slipped them into place - something that was not easy as there was a very real danger of them being ripped to shreds. Luckily they fit, though barely, and Jenny wiggled her ass as she enjoyed the feel of the thong nestling between her powerful buttocks. She knew there was no real point in searching for a bra - her DD-cup melons would be far too big to fit anything her modestly-endowed mother owned - but, just for fun, she decided to give a Wonderbra she found a go anyway. After much struggling Jenny managed to squeeze her plump breasts into the cups but her attempt to fasten the bra left it torn in half. "Oh well," thought Jenny, "It's not as if I need a bra!" Her boobs stood proudly to attention without the slightest sign of sagging anyway, courtesy of the superb muscular support offered by her pumped-up pecs. "Now," thought Jenny, speaking aloud, "I need a dress. A dress, hmm ... " She opened the massive wardrobe behind her and began to examine prospective items of clothing. After about 10 minutes of searching, she emerged from the wardrobe with her choice, "Perfect!" Jenny clapped. It was another struggle to squeeze into, but she managed it, although once again seams were stretched to bursting point. The dress she had selected was a dark silvery-grey number with a plunging, rounded neckline. Two slim straps tied behind her neck and the top half of her back was left exposed. A small zip ran up the front and was now struggling to remain fastened whilst, at the bottom, the skirt just covered Jenny's powerful butt. Virtually all of Jenny's pecs remained open to appreciation, as did her many inches of creamy, smooth cleavage - her formidable breasts were scarcely contained. Similarly, her shoulders and arms were completely uncovered, and Jenny admired them now, "I'm a super-sexy little muscle-bunny!" she giggled as she flexed. Once again, Jenny rummaged through the wardrobe, this time surfacing with a pair of kitten heels. She slipped them onto her feet and the effect was immediate and draw-dropping - her calves exploded, reaching their very limits of muscle-pumped prominence and her every movement, no matter how tiny, caused her supple young thighs to ripple ominously. "Wow!" Breathed Jenny, "I'm amazing!" Jenny began to parade up and down in front of the full-length mirror on the wardrobe door, moving like she had seen Marilyn Monroe do in so many movies. Of course, Miss Monroe was not quite so well-developed as Jenny, and every time the young girl wiggled sexily her feminine muscles erupted, something that pleased her greatly - she couldn't stop running her hands over her tight, round ass, flexing her pecs and squeezing (or at least trying to!) her immense biceps... TO BE CONTINUED...