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Shirou Emiya, a magus of incredible potential was just waking up. He yawned loudly as he stretched up his arms and got changed from his pajamas. It was the weekend, there wasn’t a lot for him to do. He decided to clean up his home a little before he heard the door bell. “Coming!” He said as he opened the door and found on one standing in the entrance. It was quite weird, he swore he just heard knocking. But the weirdest part was the package that he found in front of him. He didn’t remember waiting for any packages. He took the box into his home to open it and see what was inside. The red haired young man found something truly strange… It was some kind of dog collar, but not just any dog collar. It was from a brand named “Total Obedience”. It came with a pamphlet of their many products, but he specifically looked for the collar. He read out loud, “The ultimate shock collar to conquer them all. The most advanced training collar that will make any puppy you put this on 100% more obedient and loyal. The voltage was carefully design to not “hurt” the puppy, but instead rewire their mind entirely for full submission. Even the most bratty, and violent of puppies will love you after a single use of the collar”
He was pretty confused by the collar, he didn’t even have a dog to put this on. “I wonder if this belongs to my next door neighbor. She recently moved out so perhaps she placed the wrong direction” Shirou thought as she brought the collar with him. He didn’t know much about his new neighbor besides her appearance and how noisy she tends to be. He went and knocked on her door, waiting for her to answer. It would be the first time she talked to her so he was a bit nervous. Soon though, she opened the door. His neighbor was panting, it seems he interrupted her in the middle of exercise. “Huffff haaaa….neighbor! Sup?” Naruko greeted him.
She was a bit of an intense person who did nothing but train her body all day. A blonde beauty who made Shirou a bit flustered when she looked at her, it was hard for him not to end up staring with how curvy Naruko was. Her small waist made every other asset that her body had stand out so much more. Her breasts for example, those things were at least triplet the size of his head and would end up smothered under them if she were to trip on top of him. Her breasts were being held back by an orange sports bra that could barely contained the massive tits of Naruko, they looked like they were gonna end up spilling out any time soon. Shirou ended up staring a bit too long at her big, sweaty tits and how a droplet of sweat ran down right between her cleavage. Shirou ended up looking down out of embarrassment, but his eyes would just end up ogling at her curves.
Naruko had pretty wide, child-bearing hips. He didn’t know hips were able to get so big and fit inside a pair of tight yoga pants, with a pair of pretty thick thighs to go along. Naruko was able to keep a balanced hourglass body type. The type of body that completely turned off the mind of Shirou for a few moments before he recovered his composure. He stuttered, “N-Neighbor is this...yours? It was by house but I don’t own any p-pets…” However, when he tried his hardest to keep eye contact with her this time, Naruko just loudly laughed at him.
“PFFFFFFF! AHAHAHAHA WHAT?! Dude! Is that really the reason you came here? That’s like, such a lame excuse to come and flirt with me. Who shows up, pfff heh...With a freaking collar to someone’s house and ask “Erm is this yours”? You clearly bought that, I can tell by how nervous you are trying to pretend it isn’t yours. Could have been smoother, maybe if you brought roses or something I would have accepted them. But a collar? Pfffff! I’m not a dog, idiot!” Naruko mocked him, unable to take Shirou seriously when he held up that ridiculous collar in his hand. Shirou’s face got bright red in his fluster, being embarrassed after Naruko mocked him trying to find out who’s collar this belonged to. He just wanted to return it to their owner, but instead, was made fun of completely by his blonde bimbo of a neighbor.
Shirou was quite annoyed that his kindness was brushed off in favor of being made fun of, being this bimbo’s laughing stock really frustrated him. This was the first time they even talked to each other, nothing he did should have even trigger that reaction from her. Shirou clenched his hands, opening the collar that he had in his hands. He interrupted the laughing bimbo by placing the collar around her neck, he exclaimed, “Now you are, b-bitch! Maybe this teaches you to stop acting so spoiled” He felt relieved after placing that collar on her, being able to express his anger through mocking Naruko back by making her look like a dog with that branded collar on her neck. He turned around, ready to walk away from Naruko’s home.
His blonde, twin tailed neighbor wasn’t planning to let him go so easily. She exclaimed, “H-HEY! WHO ARE YOU CALLING A BITCH YOU—GHGHHHHGHGH?!” Naruko was stopped before she insulted him by the collar activating. The advanced collar on her neck detected signs of aggression. So any attempts at harming Shirou would send shocks against Naruko. The blonde twitched all over when shocked by the collar, she kept trying to fight back and to stop him from leaving. “GGHHHH YOU STUPID GHHGHHUGHGHGHH TAKE THIS COLLAR OFF ME BEFORE I NNGHGHGHGH OOOUUGHGHHHHHHH” Naruko tried to speak, but the more aggressive she got the more shocks she received. Her brain was being fried completely, being reduced to the size of a puppy with each shock. It was just like how the product was described, with it being capable to rewire minds and turn anyone into an obedient puppy.
Naruko eventually stopped fighting it after her brain couldn’t even form proper words. Shirou looked back at her, after she stopped moving and ended up on the floor. Shirou asked, “….Ma’am are you okay?” Naruko immediately got “back up”, however, she has completely forgotten how to walk in two legs. Naruko only moved on all fours now. And when she tried to speak it was only barks coming out of her. Shirou quickly realized that he fucked up by placing the collar on her. And their other neighbors were unlocking their doors to see what was happening. Shirou panicked and quickly picked up Naruko from the floor and took her into his house. “Shit what I have done…?! I turned my neighbor into some...weird puppy thing. First things first…” He thought while in the middle of taking off the collar off her. He didn’t want to further ruin her mind with that thing, though it was already too late. Her brain was a complete mush now, unable to have any complex thoughts and have the brain of a dog in her.
Shirou looked in the box that the collar came in, trying to find the manual to find a way to undo the puppyfication. “C’mon, it has to be somewhere around here, please….ah! Here it is, the manual for the shock collar!” He said in relief after finding it. He gave it a quick read, trying to find the section to undo it while Naruko crawled around like a dog, and instead of panting because she was tired of her exercise...she just panted from pure animal instinct. Shirou flipped through the pages, and not a single one mention anything about undoing the obedience training. They only explained more ways to train his new submissive and obedient puppy. Shirou sighed, “T-This can’t be happening...There has to be a way no? Maybe online…?” He tried to see if there were any buttons on the collar itself that he could push to undo the puppyfication, but there was nothing. And if he were to use the voltage to try and return her back to normal, he could end up turning Naruko even more stupid.
Shirou watched how Naruko walked like a dog around his house, panting as she felt so heated. She felt like her clothes were in the way, and used her last human-like neurons to strip away from her clothes. Shirou yelped as he watched his neighbor take off her top, “N-NEIGHBOR NO, KEEP IT ON! Y-YOU’RE NOT A DOG!” Naruko wouldn’t really understand what he was saying as she simply wanted to be less uncomfortable with the top hugging onto her breasts. She didn’t feel good having to keep a top so tight around her boobs. Naruko looked much happier after she tossed her stupid sports bra away. It was less hot now that she was able to let her breasts out like nature intended. She happily panted with her breasts fully exposed, nothing was holding them back now showing their true size to Shirou.
He tried to cover up his face when Naruko took off her sports bra, however, he kept peeking in and seeing just how big her breasts were. Naruko’s breasts looked even bigger out of the bra, with Shirou ogling at her nipples. It was hard for the Magus not to look at them, they wobbled around just from moving around in all fours, making them sway left and right and squeezing them together with her arms by accident. Naruko wasn’t fully comfortable just yet though, she still had those tight yoga pants hugging onto her lower body. She groaned as she took them off however she could, pushing them away off her lower body, along with her pink underwear. Naruko freed herself up from the heated pants to finally be a free and obedient puppy. “Woof!” She barked at Shirou, tongue out as she looked up at him with a wide grin on her face. It felt pretty surreal for the Magus, she went from mocking him and laughing at him to….whatever this was. He had no words to describe the absurdity of this situation, how it felt like a weird dream to see his neighbor on all fours panting and barking at him.
And since she didn’t have a tail to shake, the alternative was her ass. Shirou was shown the trained glutes of Naruko from the front, his neighbor shook them when he saw them. Shaking them rapidly left and right when she was “happy to see him”. His eyes got lost in her cheeks when they wobbled left and right so fast. Shirou clenched his hands onto the sofa when he watched her shake her ass for him, the size of her ass was just right. Being so round and heavy looking, he can only imagine how good it must feel to go balls deep into her. Shirou shook his head and said, “N-NO! I shouldn’t even humor the idea! She’s still my neighbor and it’s my fault she’s like this! I can’t take advantage of this situation it would be wrong of me…” He tried to resist Naruko in her puppy state, even after being mocked by her, he still put everyone’s interests above his own and tried not to give into the lust.
However, Naruko approached him while he was in the middle of debating against his lust. Trying not to get hard looking at his neighbor naked. Naruko, in her fried mind state would try to “Free up” her “owner” by biting the zipper in his pants. She tugged down the zipper with her teeth, revealing the erection on his underwear. When he watched her unzip his pants like that, Shirou’s cock reached full erection. Which lead to his underwear and pants being completely ripped apart by his oversized cock. His attempts to resist her were worthless once his erection was out. A cock twice the size of his torso, veiny, and already leaking precum. Naruko peeks from the side of his cock as she looked at him with a big smirk on her face and replied, “Woof woof!” at him
That was the last straw that broke Shirou, as he couldn’t keep holding back his erection for longer. He grabbed Naruko by her lovely blonde twin tails and forced his mammoth-sized cock into her jaw forced all the way down with her lips wrapped all over his cock. Even with her mouth getting stuffed full of his Shirou’s cock meat, Naruko still shook her ass left and right happily taking in his cock. He groaned, “GHGHGHGHGH FUCK, THIS IS YOUR FAULT! YOU SHOULDN’T HAVE MOCKED ME YOU LITTLE NNGNGGHHHHH” he pushed more than just his tip in her mouth, the rest of his virile Magus cock slipped down her throat. A bulge in the shape of Shirou’s cock was forming in her throat, all while Naruko’s drool started to cover at least half of his cock.
“GHHOUGHGHGHGHGGHGHOOUUFFF GHGHHHOOOUUGGGGHHHFFFF” Choked Naruko with just half of his cock in. Already, the walls of her throat were stretched so far away it made her throat feel just like an onahole around his cock. Even with a cock of this size going down her throat, Naruko was unaware what was being done to her, her mind was already mush, so getting face fucked by Shirou would only further reduce her intelligence. Despite of how thoughtful Shirou was, when he was pushed to his limits like this...He couldn’t help himself for wanting more than he already had. He tugged hard on her twin tails, using them like handle bars as he pushed Naruko all the way down his cock and hitting her stomach with his oversized cock. He stuffed not just her mouth, her throat...but also, even her stomach full of his cock only because he wanted t to feel the lips of Naruko around the base of his dick.
Shirou groaned in bliss getting a deepthroat from Naruko, his cock throbbed inside her stomach, being able to rest inside it as he watched the eyes of Naruko rolled all the way to the back of her eyes when trying to process the fact she got stuffed with countless inches of Magus meat inside her. And that was just the first thrust he made to fit his cock, Shirou proceeds to start humping her face and tugging on her twin tails to do so. He pulled Naruko back at least by half way of his cock only to tug on her twin tails again and make her kiss the base of his cock. He groaned, “GGHHGHGHHH NOT SO SPOILED NOW, HUH?! MMGGGHHHH THIS IS WHAT YOU GET FOR MOCKING ME!” Shirou knew it was wrong for him to do this to Naruko after rewiring her mind to be like an obedient puppy’s, but he couldn’t hold back any more. He had to keep his cock in check every day, to not get hard in public, and to be respectful with everyone else while neglecting the massive cock between his legs.
He refused to neglect his erection, especially with Naruko teasing him even after she became an obedient dog mentally. He was already in the middle of humping her face, and even fucking her stomach with how deep he was able to push his cock down her throat. He might as well go all the way with her now. And he sure was on the way with how he fast his hips were going while humping the face of Naruko. He made her rest her chin against his pent up churning nuts, storing so much of his jizz in them. They grew bigger and heavier when he felt pleasure, so it didn’t help that he was getting his cock slobbered by Naruko. He was already twitching hard inside her throat, the tip leaking precum directly into her stomach, not even giving Naruko a choice. He wanted to fill her up, to flood her stomach with all his pent up frustration.
Shirou felt a sudden clench on his balls, his cock immediately spurts his pent up jizz into Naruko’s gut. Her stomach was filled up to the brim in cum in a couple of seconds, the potency of his load was of a fire hydrant with the amount of jizz he was letting out into her stomach. The jizz that didn’t fit would just end up going all the way back up to cover up the walls of her throat instead, and going even further to reach her mouth and end up stuffing Naruko’s mouth full with his potent jizz. Her stomach bulged with the excess of jizz that was pushed in directly, making her stomach look as if she stuffed a massive pumpkin inside her.. All from a single load directed to her stomach, while the excess jets out from her mouth and nose alike. Torrents of jizz slipped out of her mouth, and from both of her nostrils. Naruko’s stomach sloshed full with gallons of Shirou’s cum, with her expression remaining the same as long as he kept his cock inside her mouth. “G-Ggghhh….oh, right. Sorry, neighbor” Groaned Shirou as he pulled out his cock out of her mouth, which leads to her spilling out the jizz that was stuffed in her mouth as she tried to recover her breath.
And even despite of getting face fucked, her stomach stretched out to be four times its original size, and the taste of semen all over her mouth and throat...Naruko still smiled with the semen that ran down her lips, with her respond being the same as it always has, “WOOF!” Shirou already crossed the line, so he might as well continue to see what’s beyond the line after using his neighbor as a fleshlight for his cock. He got behind Naruko, his hands placed over her cheeks. He would be lying if he said that he never wanted to get his hands on her ass cheeks whenever he watched Naruko through his window. His new neighbor had an ass way too big not to be felt up like this, his hands were sinking on all the ass meat that she had.
He spread out Naruko’s ass cheeks while kneading them. He found the tight asshole of Naruko hidden between her massive cheeks, it would been impossible to find it without spreading them wide enough for him to line up his cock properly in front of it. And despite of how small her anus was, that didn’t stop Shirou from face fucking her a few seconds ago. And since his cock was covered completely in her saliva, he was fully lubricated and ready to use his neighbor’s asshole. All it took was a single thrust, spreading apart the walls of her anus to allow his cock be inside her. Naruko groaned feeling his girth stretch her out, he managed to go all the way to even bulge her stomach once more. His oversized Magus cock managed to reach even her breasts while bulging her stomach. The cock bulge in her stomach was right between her tits, so he didn’t only get to have anal with his blonde bimbo neighbor. But be able to give himself a titfuck while he was at it.
Shirou clenched his hands on her ass cheeks to have a good hold of her before he started with the rest of his thrusts. Shirou was more than excited to do it doggy style with Naruko, she shook her ass this whole time for this, teasing him with the wobbles of her cheeks. Shirou’s hips moved on their own, slamming them back and forth and feeling all the ripples right against his crotch, it felt just as good as he imagined. With the tightening anus of hers mixed with the wobbly ass cheeks that cushion his thrusts. He bounced against Naruko’s cheeks, making them clap with the thrusts of his hips as he heard her moan when he plunged his cock balls deep into her ass. “Mmmgghghhhhh finally learned your place, bitch? I was right in calling you dog...hufffff” Shirou asked, of course he only got a bark from Naruko but that was the response he wanted to hear when fucking her from behind.
He slowly picked up the pace of his thrusts, getting his hips to move automatically as he kneads Naruko’s ass cheeks. He was still processing how it was possible that he could get his hands all over his neighbor after she mocked him. He didn’t think he would be back at his place, fucking her and correcting her behavior. She was the kind of girl that felt completely out of reach, and who was to spoiled to consider even going on a date with someone like him. Now though? She barked for him, she shook all this ass meat for his cock and he was able to ride her from behind and go balls deep into her tight anus. And Shirou enjoyed every second of it, so much so that he went and slapped her ass while in the middle of humping her. Shirou exclaimed, “TIGHTEN UP YOUR ASS!”
The slaps to her ass caught Naruko off guard, the dog-minded girl ended up tightening up in response to the slaps against her ass. She wasn’t ready to take all those slaps against her ass, the walls of her anus squeezed his cock tightly. Her anus tightens whenever he slaps her cheeks, so when he wanted her ass to really squeeze his oversized Magus meat he just slapped her ass and received what he wanted in seconds. Shirou leaked precum into her ass with how close he was to his climax, the feeling of her tightening asshole, mixed with all the softness he received from sinking his hips against her ass were all he could have asked for...And yet, he was also receiving a titfuck at the same time thanks to how far his cock was able to go he would get Naruko’s breasts massaging the stomach bulge she had. It was the result of his cock being so ridiculously huge, and that his thrusts were sending her tits swaying back and forth which turned their doggy style anal into a titfuck combo.
Shirou loved all the softness he got rewarded with from humping Naruko from behind, with all that ass for him and his hips to sink to...And his cock getting to feel the swaying breasts of Naruko while still inside her ass. The excessive pleasure eventually got to him, pushing him to his limits as his balls started to churn again. There was so much semen in his balls, he had no idea where he could even put it….aside from using his new “dog” of course. Without her he wouldn’t be able to figure out how to deal with being so pent up.. Shirou reached out for her twin tails again, and tugged on them while he fucked her, his thrusts being much shorter and faster. Shirou was so close to cumming he couldn’t hold it in for so long, and needed to hold onto her hair while he lets it all out. Her hair tugged back by the same neighbor that she mocked a few moments ago, getting her ass reshaped to the size of his absurd Magus cock right before being hit with another wave of semen.
Naruko slipped her tongue out with her mouth wide open when she felt the second wave of jizz from her “owner”. The blonde orgasms from anal, squirting on his carpet while her anus got completely flooded under the jizz of Shirou. Most of it ended up jetting out of her ass since it wasn’t possible to fit even half of his semen into her asshole...But the semen that he forced in by keeping his cock plunged into her ass? That made her already full, and large stomach become twice as large Making her stomach look bigger than her own breasts, with the obedient puppy squirting in bliss. Being fucked in every other hole ended up making her pussy wet with envy, she had all that semen stuffed in both of her holes except for the most important one. Naruko, his obedient puppy was in heat. With juices that ran down her legs as she waits for Shirou to take action.
Luckily for her, she won’t have to wait for long for him to use her cunt, that was the hole he wanted to use the most. The loads he let out were just a warm up for him to get ready do her cunt raw. There was no need for condoms, an experienced Magus was able to take the fertility of jizz for whenever they do a “mana transfer” with their servants. So, he was able to do it raw as many times as he wanted with his neighbor without any sorts of consequences, well, with the one exception that he fried her mind into becoming like a puppy’s but she visibly didn’t mind acting like a dog in front of him, that spoiled bratty Naruko wasn’t longer there but the much better and kind puppy Naruko.
Shirou placed her against her back, and got right on top of her. He was a bit “vanilla” in terms of his favorite positions, even with a cock that big he still liked the mating press more than any other position.. He grinds his erection against her pussy lips, getting ready to completely reshape her cunt. He slipped it right away, no further warning he just pushed it in and made her pussy lips spread apart to allow him in. It was already so wet, he didn’t have any issue going going balls deep into her cunt. He went all the way in until the tip of his cock met up with her cervix, he was slowly crushing it down with the tip of his cock. Going as far as possible until her stomach got stretched with the bulge of his cock.
His dick was once more getting paizuri’d by the tits of Naruko wrapped around the cock bulge in her stomach. Shirou rested right on top of Naruko, his hands placed on her breasts as he got to feel up his neighbor’s bust, the rest only lasted a few seconds since his hips immediately started swaying back and slamming forth. His balls were all the way up in the air before they came crashing down against the soft cheeks of Naruko, making ripples with every slam of his pent up nuts. Naruko’s trembled when Shirou humped her, they twitched and moved whenever she felt her cervix getting crushed by his cock which was pretty often when he rode her. Naruko was getting her guts rearranged by the countless thrusts of Shirou against her cunt, tightening the walls of her pussy when feeling his girth pressed so deep inside her.
And to think she was gonna end up like this after moving into the neighborhood, that some redhead boy would do this to her mind….To turn it completely useless while making her think like an animal with no free will. An obedient animal that loved receiving his cock, to get fucked and stretched like this, taking it all like a good puppy would. Naruko wrapped her legs around Shirou's hips, wanting to get closer to him holding onto him while feeling the many thrusts against her pussy, Naruko groaned before squirting all over his dick, reaching an orgasm easily as she panted. She felt so good taking in his cock, she begged for more by staring at him with bedroom eyes. Even when she was unable to talk or express herself like a human, her eyes should be telling him everything that he needed to know.
Shirou increased the speed of his thrusts when looking at Naruko, his balls were churning so much when she looked at him like that with no thoughts in her mind besides wanting to fuck. That and the softness of her tits against his chest when laid on top of her felt way too good. He couldn’t control his hips at all, they were reaching his max speed, thrusting with all the strength his body could put into them. Her cervix completely flatten by his cock which allowed him to thrust with much more ease and stretch her stomach more easily, all while receiving a second titfuck from her. Naruko’s bust massaged the cock bulge that went all the way up her stomach to be right between her tits, with her body in a constant movement due to his thrusts it was like she really was titfucking him.
The pent up Magus felt his balls get heavier with all the churning semen on them, every spank that he made against her ass with them, every swing...His balls were so heavy now. The spanks against her ass cheeks turned her ass bright red, proof of just how much Shirou loved to hump her down onto the floor and fuck her stupid. He pressed them down against his neighbor one more time before his nuts clenched up and released his biggest load yet. Those previous two were nothing but the warm up, the real load came out so suddenly that Naruko didn’t notice until her womb was already full. Just two ropes from his cock were enough to have her womb flooded, there was no need for more. However, Shirou already had a whole load on its way. There wasn’t anything that would stop it from going inside her womb even after getting filled up.
His jizz pushed her womb beyond the limits that it had, with him keeping his cock balls deep and not moving anywhere he managed to force the rest of his load inside and force her womb to handle a whole gallon of his jizz inside her. He was being slowly being lifted up by her growing stomach as her womb took all that semen. Naruko’s stomach finally reached the most ridiculous size she could have gotten, with her filled up stomach looking like she was stuffed with a massive beach ball. All of it being semen that sloshed inside her when Shirou poked it. Naruko was left with a satisfied, and happy expression on her face after being stuffed with so much semen. Being thankful to Shirou for cumming so much in her even if she couldn’t express it with words.