The two of them were sitting there staring at the portal, as they often did.
KC and Kaycee, two beings who could never quite rationalize their similarities, were sitting on their backsides in a clearing of grass, deep in the forests outside of KC’s city. The woods were thick to the point that anyone on the outer edge would find it impossible to see clear through, and the grass was so tall and thick, it became like a bed for weary travelers. 
Even after all of the time they now spent together, the pair often found themselves completely entranced by the milky, swirling energies that filled the onyx stones of the portal with a soft, cloudy blue hue. It was still unclear to them that this portal was the only gateway between their two dimensions, places where things were so very similar that one could wander through the portal and not know that they’d come out somewhere different on the other side, save for one difference. 
KC was a male, and lived in this dimension since his birth. Kaycee was his equal in all ways, and his opposite only in gender. Everything, from the light teal tones that made up their fur coats, their cream colored underbellies, stunning emerald eyes, and even the length of their hair was just about on par, and finding themselves to be so similar, even if they couldn’t make sense of how their worlds had come to be joined, their mutual attraction made perfect sense to them.
“I think it’s happening again, KC…I just knew it would if we came here,” Kaycee suddenly spoke up, breaking apart what had been a perfectly clear silence, save for the sounds of nature around them.
KC couldn’t help a knowing grin. “You always seem to get a little bit aroused when we come here. I guess it can’t be helped…this is where we first met, after all.”
Perhaps the only difference that existed between the two worlds existed only between the pair themselves. The first time that Kaycee burst through the portal in that moment of pure chance, KC was simply relaxing in the area around the portal, but even at their first glance, they could feel the fire that burned between them, and in the very next moment, she found that she’d gained a new ability in passing through the portal.
KC could, whenever he was truly aroused, grow exponentially in size. Much to her shock the first time that it happened, Kaycee grew so rapidly that her clothes simply ripped apart on her changing flesh, and KC grew in time with her…
Now, it was about to happen again.
On the other side of the portal, both echidnas found that they lost their ability to grow, so whenever they found themselves in the mood on KC’s side, they took quick advantage of the situation. “I can’t help it! Every time I think about the first time I came through here and saw you resting there, I get chills down my spine…remembering how your clothes just clung to your abs like a second skin, and then watching every muscle on your body get even bigger…it’s getting me hot just thinking about it!” Kaycee admitted, knowing that her bright yellow bikini and its black accents would be nothing more than tatters in a few moments. 
“You didn’t look too bad yourself, Kaycee…and you’re still wearing that same skin-tight yellow bikini I first saw you in. Almost a shame that it’s about to be nothing more than rags,” KC pointed out.
No sooner than the words were uttered than did Kaycee’s bikini top give out, harkened through the air with a harsh riiiiiiiiip! Tatters of yellow cloth shredded and fluttered down to the ground as the female echidna’s breasts started to immediately double, and then nearly triple in size, but her transformation was only just getting started. The excuse for a thong that she wore on her lower half was no match for the change, and the thin strings that kept the tight fabric clinging to her pubic mound was torn asunder with ease. 
“You never seem to remember to take your clothes off first, do ya?” KC asked, snickering quietly as he’d already started to hoist his shirt up over his head. Carelessly, he tossed it into the grass next to her, having to pick up his pace a little bit to keep from ruining his shorts and boxers. As they slid down around the toned muscles of his thighs, he paused for a moment to appreciate the wondrous sight before him; no matter how many times he watched Kaycee grow in this way, he never did tire of it. It was fascinating how every muscle and fiber of her body, even every inch of her being managed to stay in proportion as she grew, and within moments, she towered over KC, standing stark naked and tall in the forest, her upper body sticking out high above the trees. 
KC followed suit rather quickly, as the strong, toned muscles that made up his body started to expand, and he could feel the change affecting other parts of his body. His cock, already slightly engorged at the sight of his growing partner, started to fill not just with the warm blood that stiffened it, but with an unnatural size, and his legs followed suit to keep him standing upright just on two legs, instead of a third. His upper body started to grow as well, and the tight, firm abs that Kaycee so admired became larger, thicker and even more defined as the male echidna started to rise up above the canopy as well, until he stood only just faintly taller than his female counterpart. 
“I guess I always get a bit caught up in the rush of things,” Kaycee admitted bashfully. She wrapped her right arm around her abdomen and shyly clutched her left, making a balcony out of her arms to hold up and squeeze her massive breasts together. “I really can’t help it when I think about you…and how badly I want you…”
“You don’t have to wait anymore, you know,” KC reminded her. He looked into her eyes and tried to give her a gentle, comforting smile to ease her up, but couldn’t help letting his eyes wander to the canyon of cleavage that had formed between her breasts. “And I’ve got a fun idea…lay back on the treetops. They should make a really good cushion for you to rest on.”
Kaycee was a bit hesitant at first, but as she looked down upon the trees, she felt that they should support her, and certainly, weight restrictions of what she was to lay upon never stopped them from having a romp before. “Just what are you up to…?” she asked.
The moment that Kaycee’s body rested, leaves and branches delicately holding her giant form off the ground, KC went in for his target and dove atop of her, lining up a now titanic and throbbing member with the perfect gap of Kaycee’s breasts. “Just doing something with those giant tits that I know you’ll love,” KC explained bluntly, letting out a grunt of pleasure as his massive shaft rested upon the soft, supple flesh of his lover’s chest. “Mind slicking me up a little bit?”
“With pleasure,” Kaycee replied, a coy grin starting to play upon her lips as she shamelessly ogled the sizeable tool resting between her breasts. The female echidna bent her neck forward and pressed her lips upon the head of KC’s cock in an affectionate, teasing kiss, sneaking her tongue out to slurp and lick all over the tip. 
KC felt his face twisting up in pleasure, but far better, he could feel Kaycee’s expert tongue dancing upon and playing with his throbbing manhood. “Now that’s what I’m talkin’ about, baby…” came a blissful moan from the male, as little dribbles of saliva that would be like small streams to an average sized person flowed freely over the shaft of his endowment. With no hesitation, KC started sliding the girth of his massive cock between Kaycee’s mountainous breasts, making quick work of the light streams of saliva that acted as the perfect natural lubricant. 
Kaycee winked up at her lover as she caught a fresh mouthful of KC’s tip, suckling tightly upon it before she released it with a quiet pop! “Just make sure not to have too much fun, big boy…can’t have you wasting that glorious river of cum outside of me, after all!”
“I wouldn’t dream of it!” KC tried to reply simply, but a pleasured gasp twisted his response, and put an even wider grin on Kaycee’s face. Though he’d started slow, the massive male was already starting to pick up his pace, and Kaycee could feel thick rivulets of precum staining the peach fuzz fur of her breasts. “I want to see how much of my cum you can hold inside before it flows down your thighs like a waterfall…”
Two giant paws reached around KC’s back to rest upon his rump, and suddenly, Kaycee groped tight upon the muscular flesh that she found and tugged her lover’s length deep into her mouth, deep throating him with his boulder-sized testes resting atop her breasts, right between her nipples. KC found himself so deep in pleasure that he couldn’t even gasp, and Kaycee simply rumbled with appreciation as she took a deep, intimate taste of her lover, letting it last only moments longer before she pulled off and let out a breath, admiring the look of KC’s thick, stiff shaft, glistening in the sun with her saliva. “Ahh…if you’re so desperate to do that, how about you return the favor and we get this show on the road?”
“Because the last time we took this show on the road, we caused a traffic pile up and nearly got detained by the local police,” KC joked, sticking out his tongue. “But I’m more than happy to take a taste of my darling…that much I can assure you.”
With a quiet schlick, KC pulled his tree trunk of a member away from Kaycee’s moistened breasts and slipped back, kneeling down between the female echidna’s thighs. With just a quick glance, KC could already see the effects of their foreplay, as a small stream of arousal trickled down from Kaycee’s vulva, forming a small pond on the forest floor that some smaller animals were already flocking to. They drank from the water with mixed reactions, some unsure of how to feel, and others nearly drowning themselves as they tried to drink up all they could get. KC intended to do the latter.
“C’mon, KC…talk is cheap. You gonna gimme what I want or what?” Kaycee inquired at her equally gigantic lover, winking down at him to spur him on a little faster. Though she knew of no time limits in regards to their transformation of size, she’d never been one to chance it, and certainly wanted to get the most out of it that she could.
KC thought to tease Kaycee about being too demanding, but he was starting to think he wanted this even more than she did. Setting aside his trademark black cap so it wouldn’t get soaked as well, KC rested his giant paws upon Kaycee’s thighs, spreading them just a little bit further apart. The change in size didn’t mean that KC was any less tender of a lover, and he showed it as he went just to the right of Kaycee’s dripping sex first. A light, warm breath caressed over Kaycee’s sensitive flesh, and she tensed, gripping entire trees in the ground with her paws as she looked down, able to feel and now see KC planting a soft, affectionate trail of kisses along the inside of her thighs, leaving no flesh or fur untouched in his path. The closer KC got, the more intense each kiss became, and just as his tongue came to brush over the female echidna’s twitching, erect clit, he simply let out a quiet breath upon it and switched to the left thigh, drawing another trail of kisses back down the other side.
“Ooooh…damn, KC! You’re such a tease sometimes…you’re lucky I love having you down there so much!” Kaycee fumbled along with her words, trying not to let her moans get the better of them, but it was no use. KC was a master at his craft, and after making love with her as often as he had, he knew every which way to make Kaycee melt with a single touch. Such a touch, after teasing the inside of her thighs and her breasts so much, was a simple, gentle kiss upon the clit, and the moment that Kaycee went quite, KC did just that.
“Mnn...”
 KC sealed his lips over Kaycee’s clit with a quiet, pleasant moan, letting the vibrations from his mouth flow into her body, and the sensations of his kiss urged a sudden gush of arousal forth from Kaycee’s passage, staining the male’s chin with the most feminine of juices. What missed him trickled down, splashing like rain drops upon the grassy knolls at their feet. 
“KC…KC!! Fuck! Please don’t tease me anymore…fuck me hard, KC…fuck me now!!” the titanic female ordered, her hips bucking up into KC’s mouth with such force that it knocked him away, almost onto his back. The female echidna was quivering with desire, panting deeply and nearly shaking the whole forest with her spasms, and nothing was going to sate her needs now, save for a lake of her lover’s seed. 
The male echidna was never one to keep his lover waiting, and the literal stream of precum that was pouring off of the head of his mammoth endowment and down into the forest made it clear that he didn’t want to wait either. In his haste to mount Kaycee and take her, KC almost didn’t notice that some other furs had started to wander into this secluded part of the forest, and on their faces were a mixed basket of looks, some looking completely confused, others horrified by their lack of understanding, and others still looked on eagerly, as if they were rooting the giant male on. A few couples that had shown up even started to get in on the act, kissing and teasing each other as they revered the two giants like they were spirits of the forest, spreading the air of love to all who could breathe it. 
“I guess we’ll be putting on a bit of a show again, Kaycee,” KC warned his waiting lover. With just a slight adjustment, the male echidna slapped his length down upon Kaycee’s clit, giving her one last shock and tease before he adjusted his hips. The very tip of his stiff, throbbing cock met with Kaycee’s sopping wet entrance, mingling precum with feminine arousal. With a loud, audible slisch, everyone watching knew what had happened, able to hear and see the unfathomably large cock above them piercing the swollen, aroused lips of the female. “Ahhn…damn, Kaycee…how do you stay so tight? Mnn!”
The feeling of that gigantic member filling her up was just what Kaycee needed, and another quick spray of her juices was released, this time soaking her lover’s sack. Some of the onlookers that had gathered around actually stood under the stream, finding the mateship of the two titans to be something of an aphrodisiac. “It’s all for you, lover mine…don’t you dare hold back on me, KC, and don’t take it easy…give me every foot of that big, stiff cock!”
KC reached down, gripping tightly onto the female echidna’s shoulders. He’d been content to simply take a nice, easy ride in his mate and coast out to an orgasm, but at her urging, he was going to do more than just put on a show; he was going to really nail Kaycee as hard as he could. “Just don’t complain to me tomorrow…ngh…when you’re walking funny!” KC grunted, gritting his teeth as his tummy tightened, flexing his toned abs to thrust his hips into Kaycee even harder than before. Just due to their sheer size, the sound of their bodies slapping together seemed to draw even more attention, and the large frame of their motion made the trees around them bristle with an unnatural breeze.
“I wouldn’t have it any other way, my dear KC…now fuck my pussy until you just can’t take it anymore!” The female cried, still not quite getting it as hard as she had hoped. Knowing just how to get the extra mile out of him, Kaycee reached around again and grabbed hard at his toned backside, even digging her claws into the tough flesh. As deep as he was, KC managed to go even a little deeper as he felt those painful, yet tantalizing pinpricks in his rump. “Oooooh! Good boy…just like that!!”
Kaycee lifted her legs and wrapped them tight around KC’s lower back, adding a fun little twist to their missionary lovemaking, and even more importantly, keeping him from straying and wasting the pools of cum that were sure to flow soon. “I just knew you’d be begging for a good, hard dicking before too long, Kaycee…” KC taunted, pausing in his thrusts for a moment and grinning above his lover, resisting every urging that she gave him, from the claws pushing into his rump, to the skillful squeezing of Kaycee’s inner muscles around each and every foot of his oversized cock. When he could see Kaycee biting her lip near to the point of bleeding, KC gave her the relief she needed and thrust in once again, this time as hard as he could, and each second thereafter, he gave the same effort, literally plowing Kaycee into the ground as hard and fast as he liked.
“Damn! Yes! Fuck fuck fuck…KC…if you keep up like that, I’m gonna cum…I’m literally gonna drown these people in my cum!” Kaycee warned, though she had no intentions to stop riding the wave of pleasure she was on, and KC had no intentions of stopping whatsoever. The people in the clearing down below could hear every word that they said, and yet, they had no fear of such a fate, instead, they seemed to welcome the idea, as almost every single fur was either masturbating in the clearing now, or, in the case of couples, teasing one another. Some had already gone so far as to make love themselves, and it seemed the whole forest was at risk of getting lost in the throes of passion. 
KC could already feel his hips tiring from the absolutely blistering pace that his body set, and in all of the pleasure that he felt, there was a hint of kinky, almost delightful pain from his sack slapping so hard against Kaycee’s thighs with each and every thrust they shared. Precum leaked freely from his body, coating Kaycee’s insides and drooling down, all the way to her tailhole, leaving it glistening almost as brightly as the cock that released it. “Go ahead and do it, Kaycee…I can’t hold out much longer…I’m gonna fill you with so much cum, you’re gonna burst!”
Kaycee didn’t doubt that KC really could fill her to bursting, but there was no stopping it now. Her body was nothing more than a vessel of pure, blissful pleasure, and without warning, she squirted right upon KC’s cock, the spray of her juices as great as the flow of a waterfall, raining down and showering all of the onlookers who were bold enough to stay around. “Holy shit…KC! I’m cumming! Ooooh…don’t you dare stop…give me that cum!!”
As if the sensation of Kaycee spraying liquid arousal all over his mammoth member wasn’t enough, the song of moans that she unleashed set KC’s nerves on fire, and with one last, giant thrust, his body gave in, and cum completely flooded the female echidna’s well-fucked pussy. A small bulge almost certainly would have formed in her tummy, if not for the excess spilling out and down into the flooded clearing below, coating the remaining couples and voyeurs with thick, white, sticky seed. “I’m cumming, Kaycee! It feels so good…you’re so damn good! Yes!!”
Kaycee tried in vain to clench onto the length that had brought her to orgasm. The two teal blue furred bodies that rocked against the treetops were, for just a moment, nothing more than a bright blue blur, and finally, as their orgasms subsided, they slowed down enough for everyone below to make out their faces again, but they were so wrought with pleasure, they could hardly open their eyes. Kaycee whimpered and trembled as KC gave the very last of his energy with a few hard, full thrusts, sending aftershock orgasms through every nerve in Kaycee’s body. When they were finally too spent to move, KC collapsed on top of his female counterpart, crushing the trees beneath them in the act, and yet, forming the perfect bed for the pair to rest upon.
“Ahhn…ha…hopefully my baby is satisfied for another day?” KC asked, still trying to catch his breath as he nuzzled affectionately into the female echidna. 
Kaycee smiled, and a warm blush more than apparent under her cheeks. “More like for another hour or two…but something tells me you’ll be ready for a repeat performance by then, yes? It seems like our audience wants an encore!”
It was only then that the echidna pair had a grasp for how many people from the city had gathered to watch. In their blissful wanderlust, they’d completely missed the news chopper that was recording the story from the skies, the droves of people that were still coming to see what all the commotion was, and just how many people had been there already, either too stricken with fear or arousal to leave. 
“Hmm…” KC murmured, looking down over the crowd. “Maybe we should take the show downtown. I bet we could get enough people there that we could sell tickets!”
Even Kaycee couldn’t help snickering at that. “You certainly know how to make the best out of a wonderful situation, KC…”
By the looks on the faces of every onlooker, even those of the news team, it seemed pretty obvious that no one had problem with their kinky idea.