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Also, 18+ scenes from here on out, so please be over 18 before reading. 

On the second day in the woods, someone tries to catch Ash.

Ash wasn't doing anything in particular when the human burst through the underbrush, their eyes locking down onto Ash like he was a delectable catch. The human held a slight grin, eager and ready, as they frantically tried to unclip an unused Pokeball from their side.

"What are you doing?" Ash asked.

He's a bit tired, admittedly. There's been a pounding headache he's been dealing with all morning and he's beginning to feel a bit disoriented. Ash must've just rolled out the wrong side of the bed, maybe?

The trainer blinks, stopping in their tracks. Their eyes flicker back towards Ash after glancing away briefly as if confused as to the reason why Ash was speaking in the first place. Sure, he seems a bit out of place, sitting alone on a bench with his pants discarded to the side. Ash has been steadily forgetting to wear those as well.

"Trying to..." They huff out, as if it's obvious. "... catch you?"

Ash stares blankly in response. Awkwardly, the trainer shuffles into a more usual stand.

"Stop looking at me like that, this is the first time I've tried to catch anything," They grumble out scratching the side of their neck.

"But why are you trying to catch me?" Ash asks.

There's a confusion in the air, thick and heavy, that almost suffocates as the conversation trudges along. Ash has to force back the annoyance of his pounding headache to keep this conversation going.

"I..." The person lowers their hand. "Why... can't I?"

And isn't that a loaded question. It takes Ash completely off guard, because at first, he can't find any answer to it. Why? Why can't he? This made no sense. Ash shouldn't be debating the merits of attempting to catch him or not with some random trainer. This wasn't natural, or normal. Why was he...

"I'm human," Ash blurts out. He's caught sight of his fingers, all pale and human, and the words snap out of him before he can even process them. Because he is.

"Are you?"

Is he?

"I look human," Ash says, wiggling his fingers.

The trainer nods, frowning at Ash with a distant fog crowding his pupils. "I... I have a headache, I'm just going to... go..."

The trainer leaves without a second thought. Ash groans at his headache and tries not to think about how confusing the situation just was. He'd rather just forget it.

So Ash does. It's a simple background event in his vacation turned practically permanent stay in the comfortable, lush forest he and Electra have found themselves inside of. The days become a pleasant monotonous cycle of a simple forest life. Ash rolls out from his sleeping bag in his tent and scratches behind Electra's ears before he stretches whatever growing pains he has that day. Ash is surprised he's getting them again, considering he's been an adult for a while and stopped growing around four years back.

Ash rubs at his slightly pointy ears as he dips his toes into the edge of the pond, looking back towards the crystal blue sky. Being out here, just him and Electra, feels right. Just the pleasant hum of nature and the quiet, openness of solitude. A way for him to sit back, relax, and return to his roots. Ash should've been out here already ages ago. He's not sure why he didn't leave that crowded, oversaturated city sooner.

The thought tinkers away as Electra walks up to Ash, a smile tugging on her cheeks. She's got this little giddy look to her that he can't quite place, but one that warms his heart as he scratches at the tip of her tail. Electra being happy was a surefire way to make him happy. Ash would do anything for her, really. So maybe it was a good thing they moved out here. Back to where she - they, his mind added unhelpfully - belonged.

He's starting to look more like he should, Ash realizes as he draws his hand back. There are claws peeking out at his rounder fingertips. It feels more natural to have them. Did Ash ever live without them? He can't remember.

And then, the dancing begins.

At first, Ash isn't even sure if she is dancing. He's still got that lingering headache and growing (or shrinking? He feels a few inches shorter than before) pains that refuse to go away no matter what he does. All Ash knows is that Electra starts moving, and he finds that he can't look away.

A slow, sensual twirl of her hips. A flick of her tail. Ears pressed down flat against her head and a rumbling, almost silent purr broaches from the back of her throat. Electra has a sparkle in her eyes that glints with mischief and another emotion that he can't place.

It takes a moment, but when Electra wiggles and flicks her tail, it connects. She's using attract.

There's a bubbling laugh that threatens to take hold of Ash, but one that never comes to fruition. Not when the pounding headache intensifies, and the words caught in his throat can't seem to be remembered. Ash is... why would he be immune to this? He should be. Is he?

Ash has no idea. He only gives a slight smile through the whirling confusion and lets Electra finish the move. Electra looks pleased as she settles down next to him and wags her tail as if she's gotten exactly what she wanted. Ash can't help but look away with a blush, and tries frantically to quell his thumping heart.

There's an unusual feeling that settles into Ash's gut after she uses attract on him, and it's a feeling that never goes away.

Time passes. The two of them continue to spend time in the woods together as they settle into a routine. Ash quickly ran out of the food he brought, but the forest was so lush with Pokemon berries that he found no reason to complain. Especially since his nose was getting better, and sniffing out fresh berries was becoming easier and easier by the day.

And it's around that time changes really begin to take hold of Ash.

It's changes he can't necessarily describe. Because these changes were always there, right? Yet they were new. Trying to think about it too hard always gave him a rumbling headache so he continued to push the thoughts aside and focus on the present. On what was important.

More patches of fur, black and yellow, began to sprout all over his body. On his back, his now smaller feet, and even on the underside of his chin. A tail, too, had begun to grow at some point, and now was almost as long as a normal Pikachu tail should be. Whenever Ash gets too excited, the tail begins to wag and thump against his back. Which it's always done. Because Ash always had it... always should have, anyway.

Ash continues to experience growing pains despite his height shrinking more than growing. His ears, now pointy and long, are sensitive from the sudden changes, and sometimes he spends his mornings rubbing at the corners while Electra nuzzles up against him to soothe the pain.

His clothes eventually disappear entirely. Ash can't recall when he took them off and left them somewhere, but his pants one day couldn't be found, and soon enough, his underwear followed. Which made sense. He was a Pokemon. Pokemon don't really need to wear clothes.

And it makes sense when Electra starts to make sense. Slowly, her noises drift away from usual Pokemon gibberish into real, comprehensive sentences. There are mornings where Ash and her will have full-fledged conversations and others where Ash can't understand a single word from her.

Then, there's the need.

Ash has endured the horrors of puberty. He's since grown and matured as an adult, and frankly, did not want to have to go through all of that again. And yet, here he was. Constantly trying to keep himself down and steady as he lives with Electra in a little den they've claimed as their own. Masturbation has become a requirement over a simple activity for pleasure, and it wasn't too uncommon for him to wake up, hips moving against the soft bedding they've made for themselves, his underside coated in his own release. Since the two of them have begun to cuddle more often, he's had to quickly rush out and clean up his mess so she wouldn't smell it on him when she woke up, and he had to try and hope she wouldn't do anything to get him more excited.

Electra does not make it easy.

She's a tease and a flirt, constantly rubbing up against him and getting all too close when she purrs. Occasionally she'll just walk past and flick her tail, just lightly hitting his as she continues on her merry way. The more Ash becomes closer to a full Pikachu, however, the more bold she becomes.

Ash has begun to groom himself the more his fur has grown in, making sure to detangle out any knots and smooth out any stray ends that dare to stick up after another day of forging. It's not too uncommon for him and Electra to seek each other out for help, either, to reach spots the other couldn't. Which was normal, for two Pikachu's to do.

Electra is working through a rough knot of fur on Ash's shoulder from a slight tumble he took that morning as Ash wags his tail, trying desperately to mentally will himself down, down boy, and not sport a hard-on in a very shallow pool of water. He's barely been able to keep his excitement around Electra recently, especially since he's almost fully a Pikachu at this point. Other than the obvious difference in fur color, with his being a slick black instead of normal yellow.

Electra hums out, a smile tugging at her expression as she pulls back and squirms in her spot. She seemed to be contemplating something for a moment, but without any warning, she suddenly leaned down.

Ash had no time to react before the softness of her tongue pressed against the underside of his cock, and dragged upwards. Ash stifles down a sudden gasp as she laps at the tip, her eyes focused and intense, before she pulls away.

And turns right back around to wash herself.

Oh, how that does things to Ash.

He spends that entire night, from the moment she dozes off against him, jutting his hips against the leafy bedding of their den and imagining the feeling. Looping it, her attraction dance, and her intense stare in his mind until he finished in a soft whimper and shiver of his tail.

But he's still hard, and his cock throbs with need as Electra snoozes away next to him, ignorant of his need.

Experimentally, Ash leans forward, bending his now smaller body down to take a lick up his cock. He can reach from this height, but only enough to halfway deepthroat himself before his physical limits stop him.

Ash doesn't care. This is stimulation, after all, for his needy and throbbing sex. So Ash continues, letting his eyes blur and focus on his cock as he begins to fuck up into his own throat. His tail twitches as he gags around himself, humming at the taste of his own salty precum and the sight of his knot beginning to form driving him more wild than it should. His cock is thick and weighty against his tongue, and it's wet and spongy enough for Ash to fuck up into with wild, thrusting hips.

Ash doesn't think he could stop, even if Electra woke up. He's so far gone, his eyes rolling into the back of his head as his hips rocked forward in sharp, bristling thrusts. There's an animalistic need that encourages him forward, his mind whiting out any other thought than the smell of his arousal and the tightness around the head of his cock as he greedily sucks himself down.

And he cums, just like that, spilling his seed all over his tongue and splattering down his throat as Ash buries his hips as forward as he could. The liquid pools in his mouth, small dribbles of cum dripping down his cheeks and down his chin as Ash's cock spasms in his own mouth. He stays like that, for a while, letting himself soften as he gently lapped at the slit of his dick until it finally softened for good that night. Most likely to return to a needy arousal the next morning.

Ash tries to repress it over the next few days but then has to pause and ponder... ponder why exactly this was wrong for him to explore. They're both Pikachu. Whenever he looks down at his reflection, he only sees an almost complete Pikachu staring back. He's always been one. His Mother is a Raichu, as far as he can remember, and lives in some farmlands a few miles back. Electra and him have practically spent their entire lives together. Doesn't that qualify them as mates?

Right. They are mates. It just makes sense. Two adult Pokemon living in a den together means their mated. Especially since she's so intent on driving him wild.

The first time Ash experiments with this, Electra is bent over their berry collection. She's shuffling around the riper one to the back with her nose, her entire torso at a downwards slope as her behind stuck out high into the air. She's swaying her hips and looking back at him, her glistening pussy just in full view of her mate.

This time, instead of awkwardly bumbling away or running to masturbate, Ash walks forward and takes an experimental lick at her slit. At her loud and very affirmative moan, he completely buries his head between her thighs and eats her out until her release, sweet and potent, spills across his mouth and down his chin.

That begins their little sexual excursions. What went from teasing little snippets here and there slowly dissolved into entire sexual scenarios. Sometimes Electra would suddenly lean down and lick at the head until his release spurts out onto her tongue. Other times Ash would swirl his tongue around her clit until his face and her thighs were a mess of her dripping lust.

Of course, it doesn't stop there. Not when Ash is experiencing new levels of need and Electra is all too eager to reciprocate his advances. And they're mates, aren't they? This was normal. Two Pikachu's their age should've had a few eggs by this point.

One night, after taking care of his mate, he reaches over to grab his hat. His special hat that he's worn for so long, a single article of clothing that held so much importance to him.

The same article of clothing he couldn't find.

There's a pang in his heart because he cares about that hat. A staple of Ash himself. Wherever his hat went, Ash went, and vice versa. That hat, too, became a victim of his sudden increased loss of clothing. Which makes sense, he supposes, Ash shouldn't... have clothes, not for his species.

It still hurts to think about, though.

Eventually, the growing pains become worse. Specifically, one night when Ash is tossing and turning all night, his hands - or paws at this point - pressing against his forehead as he is roused from his slumber. His tail which has been growing with wags behind him.

Whatever has been happening to him, the full effects are beginning. The fur that's been slowly spreading across his skin is coming out in quick puffs as his body begins to shrink and morph more rapidly. Every day Ash had begun to look closer and closer to a Pikachu, and now, it was finally happening.

His arms and legs shrunk until they were tiny compared to before, his face widened and morphed with a sudden gasp for air from his lungs. His tail wagged and twitched as he continued to shrink and have his body redesign itself into its true form. His paws dig into the ground as he grunts, shivering away the last lingering jolts of unease from his fur as he sits there. His brain, constant with headaches, feels like mush.

"You... you're fully a Pikachu now..." Electra, his mate, breaths out from next to Ash. She nuzzles at his cheeks, his forehead, everywhere she can reach. Her arousal scent is thick in the air.

"I..." There's a bristling confusion that lingers in his head. "Who am... I?"

It's a cluster of distorted memories and logic that he can't diversify, especially as he looks down at his Pikachu-sized hands.

Electra purrs. "My mate, my wonderful mate, Ashchu," She hums, before licking his cheek and turning around. She bends her chest down towards the floor, wagging her tail as her ass presents itself to him. "The Pikachu who's going to breed me."

His cock throbs with slick arousal, and he can't find any room to argue. They have been staying here together for ages, haven't they? They are mates, plain and simple. And mates need to have eggs. His mate needed him.

Ashchu mounts onto Electra's back and slides his cock along her folds, loving the way she quivered under his touch in anticipation. She's got her back arched in a mating position, her torso pinned against the ground with her hips pressed ripe against his with need and desire. He can't smell anything other than her aroused scent as he coats his eagerness in her juices. Every little filthy noise she makes just sends a twitch of arousal down his groin.

Ashchu lets out a soft grunt of need as he slides in, loving the way her walls clench around him, wet and tight as he breaches her virginity. And the way Electra moans just forces his hips to snap forward, completely burying himself into her pussy. Electra lets out a sharp moan at his full length pressing against all of her sweet spots, and goes limp under him as she clenches down again. It's heaven. It's better than heaven.

Ashchu picks up a slow pace that's easy in speed but brutal in-depth, plunging fully into her tight and eager pussy that seems to clench around him with every thrust, as if agreeing that he should never leave her wanting insides as much as he didn't want to. The head of his cock brushes against her cervix with every thrust, and he can't help but occasionally stop and grind, deep and filling, into her to make sure she can feel it, too. He's going to fill her so full of eggs, take care of his lifelong mate...

Then there's a flicker of confusion, and Ashchu's hips halt for a moment. Wasn't there... this was... his usual headache intensifies for a second, a brief moment of his life where he could have a second to reclaim his humanity. A brief second that was gone the next, when Electra thrusts her hips back and snaps away the headache entirely as his dick throbs inside of her. And Ashchu's fate as a Pikachu forever is sealed.

Ashchu picks up the pace of their breeding, pressing his body weight against her back as his hips snap forward. There's a manic need to breed that settles into his gut as he plunges his cock forward, causing Electra to wail with need as he grows closer to finishing. Ashchu is a few thrusts away from orgasmic heaven when Electra's walls clamp down around his intruding member, and her release gushes out around his still thrusting cock.

That does it. The feeling of her cumming causes Ashchu to grunt, snapping his hips forward into her pulsating cunt and spilling his load into her ripe and fertile pussy. He feels his knot expand, her pussy clenching around him as he cums deep into her. Ashchu shivers and moans, savoring the feeling of releasing his seed while knotted. The way her insides continue to pulse around him even as she came down from her high, and the way he can just grind against her and make her cum again, again, and again while he's stuck inside of her is nothing short of perfection.

As Ashchu's knot does eventually lessen, and he pulls out of a thoroughly fucked female Pikachu, he shivers in delight at the sight of his mate. Completely tuckered out, her pussy gaping and dripping her multiple orgasms onto their shared bedding. A beautiful hue of white and blue dribbled down her thighs and pooled underneath her.

This, he decided as he mounts her again to fuck her all over again, is perfect.