Katie and Tommy stood defiantly in front of their parents, their height unfortunately diluting the effect, not even 5 feet tall yet. The twins's mouths were agape as they expressed their dismay in unison, "But Mum!! Dad!!" they howled, not quite believing what they'd heard.

Their father's tone grew firm, "Nope, I don't want to hear it, we've worked really hard for this holiday and the accomodation is excellent. You'll both be 12 next year, surely you're grown up enough to share a nice big comfy double bed without acting like children?

The twins blushed, chagrined and on the verge of tears, but they continued to protest unabated, "But Dad!!"

Their mother spoke up firmly, "Your father's right, and that's the end of it. I'd have given anything to get a nice big bed like that on holiday when I was your age, I bet you wont even be able to tell the other one is there! Now go and get your holiday things packed and get ready for bed."

Katie and Tommy slumped their shoulders in defeat, it was pointless arguing, Mum and Dad simply didn't understand. Pouting enormously, they turned, stuck their tongues out at each other and shuffled off to each of their bedrooms. With a coordinated whumpf, both their doors slammed.


****

A week later....



They were both still asleep as Tommy nestled even closer behind his sister, invading her side of the bed. It had been so hot that despite the situation and their mutual shyness, Tommy was wearing only a light t-shirt over his fur and Katie a night dress. As had happened too many times this holiday having to share the same bed, her enforced closeness to him had stoked and stoked his smouldering pubescent urges. He could be a slave to them when awake, unable to do anything except be ashamed and embaressed of his condition, and when half asleep it was even worse.

This time he wasn't even awake at all, and in the small dark hours of the morning, Tommy curled closely behind his sister, his straining nocturnal erection pressing against the fabric of her night dress. Somehow his paws snagged and fumbled at it in the right places, slipping it out of the way. The leopard gave a soft whimper as his penis found its way under Katie's tail, hit the special spot and with a push, slid all the way into the place it most belonged.

Through the fuzz of dreams Katie felt her brother's stiffness finally brush up against her vagina and then push up inside her, a drastic change to the grinding against her buttocks she'd grown used to. Still she didn't wake, the dream world held fast as Tommy huffed behind her and sank a little deeper, to the roots now, taking her virginity. There wasn't even a physical obstacle to break the moment, fortunately for both of them that part of her had been lost some years ago to gymnastic pursuits.

Tommy shivered, somehow he was still half in a dream as he spooned his warm sister in the closest embrace possible, hilted in her tight space with neither of them even aware what mating was. She was slick and growing slicker, he wasn't the only one to lose control of his body while sleeping. With a soft grunt his hips began the movement their owner couldn't yet conceive of, pulling out of Katie, then pushing back in again with a shudder.

With a moan the leopard girl curled a little, making her bottom even more available to her brother's nocturnal intromission. She began to stir, the feelings growing increasingly powerful, yet it also felt reassuring and comforting, like Tommy was meant to be doing this somehow. And it couldn't have been a better fit, as twins it seemed his length, his shape, his size, all fitted exactly to her vagina. As his small furred testicles made themselves felt against her, his penis almost hit bottom, all but filling every bit of the small space she didn't know she had.

Almost conscious of what he was doing, Tommy seemed somehow to hold back, never picking up any more speed and mating his sister like his loins must have demanded. Instead he clung to the strange half asleep state they were both in, rocking against Katie in a very gentle, steady rhythm, panting softly through his nose. His penis had never been so hard, it swelled and trembled inside her as their movements sheathed and unsheathed it in the ultimate stimulation it could recieve. The dream grew more real, beginning to reflect the growing pleasure the boy was experiencing, the growing reality of what they were doing.

Katie was panting too, but finally she was beginning to wake up, a paw moving to rub down her slit. Mild surprise registered as she felt how it was spread open and filled by something very warm, stiff and thrusting, moving slowly in and out of her. But it was such a sweet feeling, so filled, her vagina rubbed so deliciously by its passage in and out, tingling from the sensation of it swelling and throbbing. And it was such a nice embrace, the closeness and warmth of the furry body behind her, holding her as they gently bumped against her bottom.

She was beginning to piece together the feelings as Tommy started to grunt and grind even harder against her, trying to force himself deeper. Just as she'd worked out that she was curled up in bed with her 11 year old brother Tommy and he was doing something extremely naughty, it happened, he groaned and started twitching. She gasped as she felt a sudden warmth squirting deep inside her, something very wet, and she knew it could only be her brother.

Tommy shivered as the experience in his sweet dream reached a peak of unimaginable pleasure, and he began ejaculating deep inside Katie, giving her what was actually the first ejaculation of his life, fertile seed, unknowingly doing his best to impregnate her. His stiff penis worked on autopilot as it twitched rhythmically, putting more and more of his semen inside her small vagina, doing an impressive job of filling it.

The young leopard gasped as she felt Tommy continue ejaculating his small squirts within her, wet heat spreading out around her cervix as he grunted with his release. She was fully awake now, trying to take in the sensations as her brother's boyhood finally finished its rampant movements, spreading her wide around him, hot and alive. He became still now, panting lightly in his sleep, she felt his sperm trickling down her vaginal walls. Katie lay there quietly next to her brother and squirmed a bit, she was feeling light headed and fluttery.

Shifting to get comfortable, she squeaked as Tommy's erection abruptly slipped out of her with a wet sucking sound, bumping against her and leaving a sticky trail. Somehow this was dissappointing, she'd just begun to rather enjoy the feeling of him inside her. Sighing softly, Katie moved away from her brother and rolled onto her back, reclaiming a bit of her privacy.

What had just happened? She couldn't resist and moved a paw down to her crotch to check herself, shivering as she probed along her slit, feeling her spread lips and a trickle of sticky warm fluid that had to be from Tommy. Her vagina was definitely spread open, she gingerly ran her paw back up her slit and then gasped as her fingers slipped inside. Her brother's penis had been there. Right there, and it had squirted something deep inside. Nothing like this had ever happened before, she'd touched herself down there sometimes and felt the odd funny feeling, but that had been it.

She felt like she ought to be disgusted, but it had felt incredibly nice, even thrilling. Curious, Katie withdrew her paw with a little shiver, brought it up to her paw and sniffed lightly. There was her scent, already quite naughty being from her private place, but a new one too, distinctly male and quite exciting. She rubbed her fingers together and felt how slippery it was, before popping them straight in her mouth. The cub murmered softly as the taste of her brother's sperm flooded through her muzzle, a little salty and again quite male. It was no trouble to lick her paw clean.

Yawning, the lateness of the hour made itself felt, Katie could hardly keep her eyes open. She rolled onto her side and curled up, yawning again. It felt distinctly wet between her legs, almost like she'd had an accident, but something far different was to blame. Katie reached a paw down again and felt along her slit, thought about how she ought to clean herself up, and then fell into a deep sleep.


***

It was the night after their first time when Katie awoke, sleepily creeping out of bed to pee, crawling back in again a short while later. Her brother slept soundly, mercifully he didn't snore much, laying on his side curled up slightly. She lay on her side facing him and could see well enough from what little moonlight seeped through the curtains, he'd pushed the covers down and his bed t-shirt did a poor job of covering his modesty. On an impulse she reached over to him and gently pulled it up a bit, a small thrill suddenly surging through her as his modest private parts were exposed. It was the first time since their mating she'd been able to indulge her curiosity as Tommy wasn't even aware it had happened, now was too good an opportunity to miss.

Katie stared at her brother's crotch, wishing the light were a little stronger, but it would have to do. All of the outlines were clearly visible, his furry testicles nestling against his legs which were together and slightly bent. A little higher up his body and nestled right against them was his diminutive sheath, it seemed so small and cute. Her pulse began to quicken as she looked her fill, no boy had ever enjoyed this much direct attention from her, she'd never dared look this hard. Katie hadn't planned any of this, on another impulse she reached over to Tommy and touched his sheath, gasping softly as a shiver of excitement ran through her.

She glanced at her brother from time to time to check he was still soundly sleeping, letting her paws wander. His fur was so soft, especially there, warm too, the flesh underneath yielding and mobile. The shape of his sheath indicated what hid within, what had been inside her, yet it still felt so small. The cub supressed another shiver and breathed in sharply as she squeezed his sheath firmly at the top and then pulled it down, exposing her brother's flaccid penis, red and shiny. The effect was immediate and it began to swell before her very eyes, growing longer, a little redder, pulsing through his sheath which she still grasped.

Pulling it back up, it no longer contained him now as his erection grew, she pulled it down again and bit her lip as this seemed to speed things up. The yielding flesh she felt grew firmer and firmer, taking on his tapered feline shape, the hardness of it could be felt even more when she rubbed his sheath up and down. She was panting now and so was he a little, a tingle growing between her legs. After a minute, Katie looked and decided he'd got as stiff as he was going to get. So that was what he'd put in her vagina, it didn't look so small afterall. Not big, but just right, she decided.

The girl absently rubbed at her vagina with her other paw and gave a little moan, it was very damp and sensitive. Reluctantly taking her paw off her brother's penis, she looked at it a moment longer before coming to a decision. Katie rolled over onto her other side, facing away from Tommy and curling her tail over her side. Carefully she slid up closer to him, trying to bring her back against his front like they were cuddling. When they were almost together she reached between them and picked up his paw, carefully draped it over her side, edging closer still.

With a gasp she felt the moist tip of his erection bump against her tail base and stopped. Katie listened closely for his breathing, she was pretty sure he was sleeping as heavily as always, aside from a slight panting. Reassured and shivering with excitement, the leopard cub parted her legs a little, squirming closer to Tommy and a little higher up him. She could feel him sliding down under her tail, down her buttocks, lower and lower, till Katie finally reached between her legs and felt for him. Her paw found its target and she eased him through, his penis grazing along her slit towards her special place. That was it, the girl gave a deep groan of satisfaction as he caught against her and then she guided him straight into her vagina.

It felt so nice, so perfect as she nestled closer against her brother and forced him as deep as possible. His stiffness spread her vagina l walls apart, warm and pulsing, it seemed to go so deep. She felt every detail of it as she began to move against him, pulling off a little, then pushing back again, sliding his erect penis in and out. Katie wondered what kind of dreams her brother must be having?


*****


Tommy padded into their shared room after a long shower, wearing a towel, although pretty sure Katie was out. He gasped and stopped in his tracks when he saw his usually shy sister on all fours on their bed, naked in just the fur. She was looking over her shoulder at him and flipped her tail up over her back, swaying her rump in an alarming manner. Tommy blushed and didn't know where to look, a painful erection quickly tented his towel and he tried to hide the fact.

He looked at her, unable to recognise the expression of raw need on her face, "...Katie?"

The young leopardess sounded dream-like, almost like a tape slowed down, "Tommy, I need you.. Please.. Climb on my back and put it in me. Hurry!"

He gasped and cast his eyes around the room once more, trying to find sanity. But there was nothing but his sister on all fours, begging him to mount her, and his instincts agreed. Tommy's towel fell to the ground and he hurridly approached, crawling up onto the bed on all fours, his stiff willy bobbing under him. Sniffing at Katie, she hissed impatiently, motioning for him to climb up and get on with it. He drew a deep breath, shivered, and then mounted his sister, unsure what or why he was even doing.

She groaned in delight, encouraging him forward and then reaching back to grasp his stiff penis and guide it into her. He groaned, still not quite sure what was going on, leaning forward onto her. That was all it took, she gave a cry as his stiff erection pushed its way into her. With a grunt he found himself hilted and shivered, his willy giving great twitches of arousal and excitement.

Tommy suddenly gave a whimper and dug his claws into the bed as, trembling, he began jetting his cub sperm into his sister. It was the most pleasurable thing in the world as his penis jerked again and again, spitting its slippery mess, filling her, drenching her vaginal walls as his tail flagged up high.

***

The young leopard woke up on his side with his paws around his sister, still ejaculating, and that's when to his horror, he realised he'd been dreaming, and yet he was actually doing this to Katie for real. Not only that, he was really squirting in her too, and he wasn't even sure what it was.

Katie gasped as she felt Tommy stir and actually wake up this time, he gasped in response, the reality of the situation rapidly becoming apparent. She'd been responsible this time, touching him in his sleep, then guiding him into her vagina. Tommy had done the rest, and just like before, he'd put his penis up her and was squirting all his mess all over again. It was a feeling Katie discovered she liked rather too much, especially as she'd caused it this time, the leopardess tried to suppress a shiver as she felt her brother continue ejaculating. Moaning lightly, she reached a paw down her crotch and felt their connection like before, this time feeling how each time Tommy's penis twitched and surged a corresponding squirt of warmth could be felt deep in her.

He'd put enough up her again to almost guarantee a fertile leopard would become pregnant, were the pair even aware of such risks. Tommy had mated his sister for the second time, and this time they both knew it. Eventually he grew still, panting lightly through his nose as his mating was finally complete, a sizeable pool of sticky wet semen around the tip of his penis.

As Katie felt her brother's stuff begin to slowly leak and trickle out of her, neither of them said a word or even acknowledged the other's presence. She felt Tommy softening a bit, relaxing, his breathing slowing down, while unfortunately the experience left her with an itch deep inside she really needed to scratch this time. Sighing a bit and squirming in their close embrace, she abrubtly noticed her brother had fallen back asleep.

Katie rolled her eyes and snuggled closer to Tommy anyway, giving a soft gasp she felt his slender penis slide deeper up her. It was all wet and sticky, she could feel it spreading around him, a most delicious feeling. Sadly he was still growing soft, she tried to squeeze on him but didn't really have the knack. Snuggling as close as she could, it was just putting off the inevitable. A few minutes later, the girl gasped as her brother slipped out of her and his penis slid back into his sheath.

He was dead weight now and she reluctantly wriggled free of their embrace, scooting back to her side of the bed and rolling onto her back. A sudden shiver ran through her as what they'd done really began to sink in now. He'd put his willy in her again, squirted her full of sticky again, but would he remember waking up? She didn't want to think about it and moved her paws down to check herself instead. Like before, her slit was spread open where he'd just been, oozing his warm semen. She ran her paws down either side and then spread herself wider, grunting softly at the naughty feelings.

Something was going on down there she couldn't ignore, not this time. Biting her lip, Katie slid a paw down her slit and then pushed two fingers inside, groaning as they entered her vagina where her brother had been. He'd made quite a mess, she panted softly as she moved her fingers around, slick with his cub sperm. The girl had never explored herself before, not like this, it was thrilling and made her almost dizzy. Her fingers weren't the same as him, not nearly so nice, but they were hers and she could feel a great deal more. Suddenly her thumb bumped against something very sensitive, hidden near the top of her slit, she almost screamed. It was so sensitive she could barely touch it, Katie scooped up some of the fluids she was leaking and gingerly spread them over it.

How had she not noticed this part of her before? Huffing and panting now, she was moving her paw in and out, everything very slick, bumping her sensitive spot whenever she could stand it. The rush of pleasure was like a tidal wave, growing and growing, unstoppable and threatening to overwhelm her. As Katie continued masturbating with her brother's seed, the pleasure took over and she rolled onto her side. With a whimper the cub curled up and then started to make soft chirping noises as an unimaginable pleasure exploded in her groin and spread out in shockwaves. Convulsing, twitching, she almost felt like she was dying or that she'd pass out, it was so intense. Katie finally began to get an inkling of what Tommy might be going through when he reached his peak.

It seemed a long time before the world came spinning back to her and she was left panting and shivering in a ball. Sleepyness began to return with a vengeance and she stretched out luxuriously, finishing with a yawn. The girl felt quite satisfied and closed her eyes, thinking again about how she needed to clean up. A minute later, she was asleep.