 
 
The drone of the SUV was almost hypnotic as it thundered down the lonely roads through the night.  Bright lights of passing cars shone regularly through the windows and punctuated the darkness from time to time.  The cubs were both sleepy and Tommy was the first to lay down, curling up on the wide seat and covering himself with the blanket.  Katie looked jealously at him for a while, there was no way they could both lay down, except..

"Move up a bit Tommy, let your sister lie down too," she said sleepily, lifting up his blanket.  There was room, if they didn't mind a cuddle, and so Katie wriggled onto the seat alongside him.  They ended up spooning, Tommy against the seat back, Katie in front of her, he sleepily put his arms around her and moved the blanket back down to cover them both.

It was still something he wasn't fully comfortable with yet, but at this point, Tommy was too sleepy to care.  Mum and Dad glanced back and smiled, they did look a cute pair, all snuggled up like that.  For a time, he hovered between sleep and awake, the sound of the road fading in and out, in and out.  Some time later, Tommy suddenly awoke, a little disoriented, some bump or noise had roused him.  Blushing, the cub noticed he had a completely inappropriate erection, digging into his sister, as bad a case of morning wood as he could remember.  He was trapped and could do nothing for fear of disturbing his sister, who seemed to be deeply asleep in his paws.  

Tommy grunted softly and just tried to sleep for a while, maybe it would go away again.  Unfortunately it only seemed to get worse, their embrace was so tight, squeezing him between the chair back and his sister's warm body.  Things were actually getting painful, his penis was snagged in his shorts, Tommy grunted and tried to reach under the blankets and between them.  Straining, trying to create a space, the cub fumbled at his shorts, pulling until at last the buttons came undone.  He sighed with relief, but it was short lived, now the buttons grazed against his underwear and it was almost as uncomfortable.  So be it, Tommy stuck his tongue out in concentration, lifted his hips up a bit and then eased his shorts down until they were over his knees.  Finally comfortable, he rested against his sister, underwear tented quite naughtily.

After some time, he was forced to admit it still wasn't going away, and maybe he wanted to touch it anyway, perhaps that would help.  Still Katie seemed to be sleeping peacefully, and so he wriggled a paw down between them and snagged at his briefs.  It took a while slipping them off his erection without too much discomfort, but finally he pushed them down his legs and then he was free.  Now, Tommy tried easing his paw down there to touch himself, and gave a little shiver as his fingers closed round his sheath.  He stroked it a few times and shivered again, but it was such an awkward angle it felt like his paw was going to break.  There was just no room to be doing anything except poke his sister.

Tommy chuckled at himself, and at the thought, giving up for the time being.  Instead he settled back down, put his paws around his sister and hugged her tightly from behind.  As he knew it would, his erection pressed against her, squeezed between their bodies, Katie began to stir.  He murmured softly, oblivious, making a furrow in her skirt where her soft buttocks met.  It wasn't what he needed, but it felt good, some dim memories came to mind of him doing this to Katie on the edges of sleep, on holiday.  He shifted on the seat and then hugged her tighter, letting out a little groan.

"Tommy?"  His sister whispered sleepily in his ear, inaudible to their parents.  She shifted now, moving against him as she stretched a spotty arm and leg out, yawning.  Katie pushed back against him, "Tommy, is that..  Are you..?"

Tommy mumbled an affirmative, blushing in the dark, he could hardly deny it.  The boy rested his muzzle against his sister's, still holding her, still poking her.

She chuckled very quietly, "Oh Tommy..  Can't cuddle your sister for five minutes without.."  Katie wriggled again, curious.  She lifted her arm up and reached behind her, wanting to feel just how badly he was tenting his shorts.  For a moment she was confused, his shorts weren't in the right place, and they felt unbuttoned..  But her paw kept on wandering and all of a sudden she found it, stifling a gasp as she felt soft warm fur and then the stiff shape of his erection.  That's why it was digging into her so well, why it was hard to ignore, Katie couldn't resist grasping his furry sheath briefly and squeezing it.  Now it was Tommy's turn to stifle a gasp as she brought her paw back, smiling with amusement.

She whispered again, "Sheesh Tommy..  It was that bad, huh?  Couldn't wait till we got home?

Tommy shook his head, still blushing.  After a long pause, he whispered something so quiet that even she couldn't hear, pushing against her with a little shiver.

Katie grunted softly, it was kinda nice feeling his stiffy up against her, though completely inappropriate where they were, "I didn't catch that Tommy.  Speak up a lil'?"

He paused again for a long time, as if working up the courage.  Finally, stammering, he whispered in her ear, "I want to..  I w-want to put m-my..  I want to put my willy in you."  The young leopard tucked his muzzle up against his sister's, cheeks burning, terrified of her response.

Katie was silent for a while, then she chuckled, reaching up to stroke the side of his muzzle affectionately, "Aww Tommy..  You know I would, but not here.  Are you crazy?  Mum and dad are just there!"  As if she had heard, Mum picked the next moment to turn and then glance at the cubs, seeing if they were okay.  Tommy and Katie squeezed their eyes shut and lay locked in their sweet embrace, everything hidden by the blanket.  After a moment Mum smiled, apparently satisfied, and turned back to the road once more.

Katie squirmed a little and hissed at her brother after a short delay, whispering, "See!  We should be home in a few hours so just.. contain yourself."  Her brother responded by grinding into her even more, whimpering slightly, and she rolled her eyes, "You're pathetic, you know that?".  Still he said nothing.  She thought hard for a moment, watched their parents, they were listening to music and talking about nothing.  Tommy pushed his stiff penis against her again, and she came to a decision, "I'm gonna regret this..  But I'm willing to help you out, just a 'lil, but you gotta do what I tell you."  

She squirmed again, getting a little flush of excitement as she put her paws down under the blanket and hooked her thumbs into the waistband of her skirt.  The girl paused, craning her neck to look back at Tommy as she whispered, "Now listen, I don't want you making a mess of my skirt, so..  You can put it between my legs instead," she paused, swallowing, "but that's all.  Don't get any funny ideas!"  With that, Katie wriggled a little away from her brother, arched her hips up off the seat and then pushed her skirt and panties down to her knees in one smooth motion.  Next, she settled back against him and stifled a gasp as she felt his hardness poke at her warm slit.  Katie bit her lip and wriggled up the seat until she felt him slip between her legs.  Finally she lifted her leg up slightly and made a space for him, bracing one foot against the other, pushing back into the embrace and making them both murmur with pleasure as he slid into her space.

Tommy was panting in her ear, as quiet as he could, shivering too.  She tensed as she felt the base of his furry sheath tickle her slit and his sensitive testes brush against her legs.  It was a dramatic change from being clothed a moment ago, the intimate contact made it all the more real, all the more exciting.  Her brother licked at her ears and hugged against her, straining, squashing their bodies even closer together.  After a little while he pulled back, both his sheath and his erection grazing her most sensitive place, before pushing between her legs again.  She put her paw over one of his and shivered a bit, whispering as if to herself, "You really want this, don't you?"

As if in response, he made another slow and exquisite thrust, the warmth of his penis noticeable as it rubbed up her vagina, apparently unavoidable.  She bit her lip and hadn't planned on this, her body responding to the situation and her brother's intimate contact.  He never sped up, never squeezed her any tighter, just shivered as he gently rocked in and out of her surrogate vagina.  Katie groaned now, quietly, she could feel herself getting wet inside, and she thought maybe she'd felt a trace of sticky from her brother too.  Tommy shifted slightly, completed another thrust and then she stifled a gasp as he caught in her slit for an instant before coming to rest.  She wanted to scold him but was unable to speak, briefly consumed by the growing tingling coming from between her legs.

Beads of her moisture began to leak suddenly, rubbing on her brother's erection as he withdrew.  He slid back in and it was even worse, this time his tip went right into her, becoming instantly wetter and shinier.  Shivering and apologising, he withdrew and eventually found her space, his penis coming to rest against her slit after a moment.  She said nothing and they both lay together, panting softly, eyes wide and alert as they scanned the seats in front.  Tommy pulled out again after a moment, becoming quite slick from his sister's excitement, and then pushed, and again his tip caught in her.  He withdrew, but then entered her again after a short pause, slipping a little deeper.  She whimpered and he apologised again, withdrawing.  Trying again, the cub found himself deeper still, shivering as he was a few inches inside his sister now.  Tommy shook his head and groaned, determined to get this right, pulling out and then thrusting another inch into Katie, finding her vagina very slick and warm.  It was no good, Tommy gripped Katie, whimpered into her ears as he pushed deeper still, and that's when he found he could get no deeper.  

Her brother's balls came to rest against her and Katie knew it was done, despite her best intentions.  She'd looked up mating in a book that morning, and now the anatomical diagrams suddenly came to mind.  A neat cross-section of a boy, a girl, and finally a third showing how it would all fit during mating.  This one fascinated her, a lot she had already guessed from the times with her brother, but there was so much more to it than that.  It was Tommy's stiff red penis she saw in the diagram now, filling her vagina nearly to the end.  Beyond that, her cervix, and after that, her womb.  Now the diagram changed, matching what she'd read.  She saw great viscous whorls of semen pump out of his tip, filling up any space left in her vagina.  Almost straight away, this began seeping through her cervix and flowing into her womb, where it found its way up the sides and into her tubes.  The rest of the detail was sketchy, but the important point was, if his sperm reached her egg, that could be the start of a new cub growing within her.

She shivered, it sounded amazing and made Tommy's sticky gift all the more special, it had such purpose..  But she didn't want to get pregnant, and so they'd have to do something.  What the hell were they doing right now?  Tommy trembled against her and she felt him twitch powerfully inside, he was still as deep as he could get.  Katie tried to hold back, but after a moment she couldn't help it, squeezing down on his lovely erection.  He gurgled faintly and twitched again, swelling faintly in her, she felt his tail flop rhythmically against her leg.  This had to stop, she would make him stop, but in just a little while.  She felt him surge again, a deep shiver going through his body, his breathing sounded laboured in her ears.  Another involuntary squeeze from her and he gasped, a little too loudly.

Mum turned to check on the cubs and smiled as they looked so sweet together, cuddled under their blanket, sleepy eyes but not quite asleep.  Katie forced a weak smile and glanced up at her mum as she felt Tommy start to twitch and surge faster and faster in her.  He closed his eyes and pretended to be sleepy as he gripped his sister, trying not to snort and groan as his testicles drew up against his body.  Katie felt it keenly and knew at once there was nothing she could do, as his penis twitched a final time then seemed to stop.  A moment later she felt him exhale across her cheek and begin pulsing rhythmically, and as Mum looked on, Tommy set about filling his sister with his sperm.

She didn't look away for a while, and Katie could feel the familiar wet warmth blooming inside her, the heat spreading like ink on blotting paper as her brother ejaculated.  She saw the diagram again, saw how each jet of his semen would be splashing against her tight cervix, tempting fate as her vagina filled up with his warm fluid.  Tommy could be making her pregnant and he didn't even know it, the thought of it sent a sudden ripple of excitement from her nose to her tail.  Mum finally looked away, and Katie stuffed her paw into her muzzle, letting out a muffled cry, grinding against her brother.  Whimpering, she joined in his release, shaking and trembling, her vagina squeezing as Tommy made it wetter and wetter.  Their tails wriggled ceaselessly against each other as both cubs shook with pleasure, Tommy couldn't seem to stop as his sister all but milked him.

Eventually he did though, and then they were spent, laying pressed against each other on the car seat, just shivering every now and then.  Tommy could feel the wetness like the first time, deep inside his sister where he'd put it.  It was such a relief, he sighed happily and started breathing more normally, the situation slowly dawning on him.  His erection didn't wilt for now, seemingly content to remain, jerking occasionally with an accompanying sharp intake of breath by the cub.  So there they were, an 11 year old boy with his penis deep inside his twin sister, where he had just mated her on the back seat of Mum and Dad's SUV driving through the night.  Less than 2 feet away from them both.  She was right, he was crazy, but how could he resist when his willy had felt so good?  Tommy exhaled and snuggled as close to Katie as he could, suddenly feeling so very sleepy.  Within a few minutes, both cubs were asleep.

The noises of the road and the car drifted in and out of their awareness as they both slept and dozed, very comfortable.  Katie could feel her brother still inside her as she woke for a moment, soft now, but pinned by their bodies pressed so close together.  She was asleep again, for what could have been minutes, hours, and then she became aware of his stiff erection filling her this time, the girl murmured and closed her eyes, soon drifting off once more.  This went on for some time, he was soft again, erect a few times, and finally she woke a little more fully to find him flaccid inside her like before.  Katie yawned and stretched out a little, tensing her muscles and shifting, she heard Tommy stir.  And then she felt him stir, he was getting an erection inside her and she could feel it happening.

This was suddenly a real thrill to her, Katie gave a little whimper as she felt Tommy's penis growing, creeping deeper and deeper inside her vagina as it pulsed in time to his heart.  It was spreading her open like nothing had before, getting wider and longer, more firm, more warm, a quite delicious feeling.  Then she felt it give a powerful twitch and Tommy groaned behind her, waking up more fully.  He yawned too and stretched in the confined space, groaning with the rush of feeling this sent through his penis.  It was still wet, he could feel it, the cloying sensation of his recently deposited semen spreading over it.  A shiver ran through him and Tommy started to wonder if he might make her wet a second time

After cuddling for a few minutes, the boy suddenly drew back and began mating his sister once again, short little thrusts this time, each one a little wetter than the last.  She had kept all of his sperm safe and warm while they slept but it was leaking now, clinging to his thrusting penis, lubricating it luxuriously.  Nothing had felt quite this slippery before and Tommy shuddered, speeding up his boyish rutting, clinging to Katie as he penetrated her.  Their parents were talking, he barely noticed, but the SUV did seem to be slowing down and going round a lot of corners now.  The twins slid around a little on the seat, quite disconcertingly, but Tommy didn't mind.  Katie was trying to whisper something to him, but all that seemed important this moment was pushing his sensitive erection in and out of her, in and out.

She whispered again, a little too loudly, "Tommy!"  But he merely licked her cheek and went on thrusting wetly, nodding.  Katie began to struggle now as the car slowed down further, quiet residential roads, and still Tommy would not be put off.  He hugged her closer to him, shuddering with excitement, marvelling at his sister's mutual excitement this time.  The leaking fluids were making quite a mess of their fur as they mated, seeping out of her, driven out by the motion of his penis.  Tommy began to gasp, it felt simply too good and he knew he was about to do it again.  Katie struggled and he groaned, pushing deep inside her and suddenly stopping.  A single whimper escaped her lips and a moment later Tommy started squirting, powerful jets of warm sperm painting the depths of her vagina, adding to his previous insemination.  

The SUV rumbled along a little further, then came to a shocking stop, making both cubs look round, "Wake up sleepyheads!  We're home!"  Mum and Dad gestured at them and then turned back to the front, collecting up their things.  Tommy continued ejaculating, helpless at this point, twitching and tensing against his sister as the bliss rushed through him.  She was feigning waking up now, trying to yawn and stretch, blinking as the bright interior light suddenly illuminated them both.  Only the thin blanket hid the fact of their carnal act, the merest twitching of the fabric giving away Tommy's cresting orgasm.

Katie ran out of patience and with a gasp, wriggled free, biting her lip as she felt Tommy squirt messily under her tail.  Fortunately he was all but done, she pulled her panties up and then her skirt, feeling the fabric between her legs become instantly saturated.  With a quick check to see all was well, Katie rolled out from under the blanket and left her brother gently oozing, picking up her things quickly.  As she smoothed her skirt down, he was still laying there, the cub hissed at him and nudged him in the ribs.  Tommy grumbled and finally started to do something, fiddling and struggling with his clothes for what seemed like forever.  While she waited, Katie could feel it start leaking out of her, she shivered and sat uncomfortably on the seat.

Finally they were all packed up and their parents let them out, bleary eyed onto the front drive.  The bright security light of their home shone uncomfortably in their eyes, familiar but unwelcome, pointing the way.  Katie shivered again and stifled a gasp as she felt a trickle of Tommy's semen run lewdly down the back of one leg, suddenly walking very stiffly behind everyone.  It was too much, she couldn't believe he'd put it up her a second time, she shouldn't have let things go so far.  The thought of impregnation fluttered across her thoughts and she put a paw up to her muzzle, everything was just piling on the risks.  Or were they both too young?  She really needed to read more.

Tommy hung back as the family approached their front door, luggage in tow, she caught his eye and flashed a glare at him.  But the look softened when she saw how rumpled he looked, how groggy they both were, and was that a wet spot she could see on the front of his shorts?  The front door was open at last and Katie brushed past him suddenly, hobbling, desperate to get to her room.  Tommy looked and blushed as he saw the unmistakable evidence of his sperm leaking down her leg, caught for an instant in the halogen glare.  Then she was gone, thundering upstairs and into her room before Mum and Dad had even put their suitcases down.  The three exchanged quizzical glances and then Tommy came inside, home at last.

He was fading fast and after a few goodnight kisses, the boy went upstairs and into his own room.  Everything was as he'd left it, a typical boy's room, and typically messy.  The bed called to him and the young leopard stripped, pausing as he remembered the sticky mess in his underwear.  This was new, something he'd not experienced before the fateful holiday, before everything changed.  Tommy found a towel on the floor and rubbed the fur as best he could, there would be no avoiding the shower in the morning.  Finally, blissfully, he slipped into bed, a little cold but too sleepy to care.  Cuddling his favourite lion plushie, Tommy snuggled under the blankets and fell asleep.
