Chapter 1: Before the Fall
Rarity requested Rainbow to do some errands while preparing for the Grand Galloping Gala. She sent her to look for "the most dazzling flowers in all of Ponyville," Rainbow Dash knew that her beauty-obsessed friend had a very picky taste, but regardless, she was up to the task! As she walked through the grassy streets, she passed by many beautiful showcases of dresses, hats, and what Rarity had sent her to find from the start: flowers. However, she knew there were even better flowers up on the hill by CuddleCloud Emporium, the biggest foal store in Equestria!
As she approached the top of the hill, she had a funny feeling in her stomach, thinking about CuddleCloud Emporiums' contents right by Petal Haven Boutique. There was a massive array of diapers, pacifiers, baby clothes, and stuffed animals. The mere thought of them almost put Rainbow Dash into a whirl. These feelings were new to her and they were particularly strong. Her pony pussy began to drip from the ideas circulating in her mind. She envisioned herself nestled in a soiled, full diaper, whimsically playing with her toys and allowing droplets of drool to escape her pacifier. "M-m-mama," She muttered while drooling slightly.
"Hey, Rainbow," Applejack, her long-time farm-loving friend, said. Her friend awoke her from her dreamy haze, quickly realigning herself to the straight-edge pony everyone expected her to be.
"Oh! H-hi Applejack. I was just walking around and looking for flowers for Rarity." Rainbow replied, slightly flustered.
"You seem to be at the perfect place! Petal Palace is the best place for flowers in Equestria. It ought to fulfill Rarity's need!" Applejack remarked.
Dash looked to her right, trying her best to ignore the sight that had caused her to fall into a horny daze. "Oh! Perfect! Thank you, Applejack!" "It's no problem. I'll be heading my way, but good luck with Rarity! I know she can be a real headache." "Yeah, she sure can be," Dash replied. Seeing the sun begin to fall, she quickly went into the flower shop to retrieve the flowers Rarity needed before heading back to her place as soon as possible.
Rainbow Dash dashed towards Rarity's place and knocked on the front door, which Rarity promptly opened. "Hi darling, did you find the flowers I requested?" "I sure did, Rarity. These purple and blue flowers would compliment your ball gown perfectly!"
"Thank you, dear. These flowers are gorgeous! I could not imagine a better match with my dress! I have a dress for you that will match you perfectly tonight."
"Thanks, Rarity. I'm not too big on fancy parties, but since I don't have anything going on, I guess I could enjoy a night with my best friend!" Replied Rainbow Dash. While she hadn't cared much for fancy dances and balls, the Grand Galloping Gala seemed intriguing from the bits she had seen on TV, in magazines, and elsewhere. It always seemed a bit too upper-class for her, but after receiving such an incredible present, she felt it was obligatory to accompany her friend.
She quickly threw on the rainbow-patterned dress that perfectly matched her punk-rock attitude and colorful mane. The pony looked in the mirror and promptly loved the dress. She dashed towards Rarity and thanked her for the gift. "This dress is awesome, Rarity!" Remarked Rainbow. "You guys ready?" Spike asked "Yep!" replied Rainbow and Rarity in unison. "Alright then. Hyaa!" Spike's fervent cry pierced the air, urging the carriage horses into a thunderous gallop. And like that, the two ponies embarked on an exciting journey to the most significant gathering in Ponyville. Their hearts were racing as they imagined the beautiful scenery of the ball and the familiar ponies awaiting their arrival.
Chapter 2: The Party
As the ponies arrived at the Grand Galloping Gala, their eyes became fixated on the beautiful lights and art that draped the surroundings of the ball. The sheer beauty of it all brought great joy to the two as the horses galloped the carriage closer. They finally stopped and stepped out. "We're finally here!" Rarity said, with a great smile adorning her face. Despite the Grand Galloping Gala being a routine trip for her, she could still find a way to find something to awe over. It was an event almost made with Rarity in mind. Everything brought joy to Rarity, from the beautiful dresses and suits that adorned the ponies to the fabulous designs of the glass figures and stained windows on the walls. She was, for all intents and purposes, in heaven.
As the duo walked through the entrance, Rainbow Dash spotted a friend of hers, Twilight Sparkle, and swiftly dashed towards her. "Yo, twilight! How's it going?" "Oh, Rainbow Dash. It's good to see you. It's going great. I've only been here for about 10 minutes, and I'm already having a wonderful time. It just got even better now that I know my best friend is here!" says Twilight. The two ponies looked at each other with delight. They walked towards the confections table and indulged in chocolate-dipped caramel balls and sweet orange Fuzz. As they finished, they walked close to the dance floor and idly watched as the ponies danced to classical music. Their eyes gazed across the place as their minds wandered off. Twilight couldn't help but admire the beautiful scenery. While Rainbow's mind had drifted off into the thoughts she had earlier, of being a dumb baby, of never having to appear "cool," of everyone seeing her as nothing but a mentally retarded, diaper-filling baby. She had visions of her laying on a changing table, having her butt wiped by a teacher as she drooled and babbled, not having a single thought in her head. Sucking on her hooves as she let out a gush of pee into her fresh diape-
"Hey, Dash. I think it's time to start heading home. Are you feeling okay?" Rarity asked, Rainbow jumped, flustered and startled by the sudden interruption. "Oh y-y-yeah, I was just... thinking about.. things. But yeah, I-I agree. It's starting to get late, and I'm getting a bit tired, so let's go home. Bye, Twilight!" j The two ponies waved goodbye to their friends and headed toward the carriage. "You gals ready to go home?" "Yep. I'm poofed from all of the dancing, people, and overwhelmingly beautiful scenery," remarked Rarity. The two friends entered the carriage and rode off into the night, awaiting their arrival home. They tightened their grip on their booth as they rode through the unusually bumpy terrain. But as they turned to the right, a sharp pain unexpectedly ran through the back of the left horse, causing it to start running even faster. The two girls tried their best to hold tight until a big rock hit the top left wheel, sending them out of the window. Rarity fell on a branch, only scraping her left arm, while Rainbow Dash was sent straight into a big hard rock, hitting her head and leaving her completely unconscious.
Chapter 3: Oh no...
"D-d-dash? Oh.. no. SPIKE CALL AN AMBULANCE!" cried Rarity Spike rushed to pull out his phone to call for the nearest ambulance. They swiftly arrived and took Rainbow Dash into the ER. Small droplets of blood accented her heavily bruised head. The doctors quickly assessed the damage and ensured no damage elsewhere. They put her in a diaper to ensure the sheets stay as clean as possible while she's unconscious.
A few hours later.
"S-so how bad is it?" asked Rarity.
"Well, there doesn't seem to be any significant damage, so unless there's something that we missed, she should be fine and awake relatively soon."
"Oh, thank goodness. I was worried that Dash may have suffered some sort of brain damage or... something that could have changed her forever." Rainbow Dash slowly awoke as this conversation happened and gradually became aware of her surroundings. The cold hospital air, the sterile scent, the soft sheets on her bed, and her diaper. As she became aware of the diaper taped around her waist, the thoughts that she once tried to keep hidden came back in full force. She heard them talk about the possibility of her "changing," the possibility of her entire personality essentially being erased. And her hornyness SKYROCKETED.
Before she even spoke her first word, she slowly moved her hooves to rub her diaper and started to feel a tinge in her bladder, giving her the sign to let go, so she did. Warmth quickly spread throughout her diaper as she began to let a little drool escape her mouth.
"What if I just made everyone think I was just a stupid infant now? Maybe the damage WAS worse than they thought, and they never realized." She began to think. She pushed as hard as she could into her diaper, causing the diaper and her pussy to leak. The doctor and Rarity entered the room.
I believe she's awake. She should be able to hear you," said the doctor.
"Rainbow Dash! Are you ok? Can you hear me?" Rainbow Dash forms an idea in her head and then opens her eyes. She slowly turns to Rarity, a smile creeping across Rarity's face.
"Hufufufooo," babbled Rainbow as she pushed as hard as she could, loudly grunting and gurgling as loads of warm mush enter the seat of her diaper. Her diaper seat began to bulge out, filling the once clean and dry diaper with even more pee and poop, The sensation of poop filling her diaper sends her even deeper into a horny haze. Her pussy began to drip more and more, sending her closer and closer to the edge. She started to moan and babble, watching her friend discover her true self.
"R-R-RAINBOW WHAT HAPPENED??" Rarity screamed, with tears in her eyes.
"Ahbuhguguguhububooooo," babbles Rainbow as she pushes her hooves into her mouth, blowing raspberries as the last of her poop deposited into her full diaper. Rarity's cries intensified, causing Dashy's pussy to leak even more as her new place as a brain dead drooling infant solidifies. Rarity can only sit there and look on in despair and horror, seeing her once best friend reduced to a mentally disabled diaperslut.
"There is no coming back from this." swiftly crosses her mind. This broke Dashy. She knew that if she were to go back to her old self, she'd be shunned for pretending to have brain damage. She had no choice but to continue to live out her greatest fantasy. Her loud drooly moan filled the room, making herp sound completely indistinguishable from the mentally deficient patients across the hall. Cum filled her already full diaper, causing it to leak all the while sending Dash into bliss. She stared back at Rarity with a drool-covered smile, panting heavily and gurgling solidifying that she was never going back because she was in heaven.
"I can change her." The nurse said in a sympathetic tone, guiding the distraught Rarity out of the room before getting to work changing her patients dirty diaper.
Chapter 4: Daycare
Click clack click clack was the noise that filled the daycare room. After the stunt she pulled at the hospital, her friends decided the best course of action was to put Dashy in a daycare. She was put in a small room isolated from the other foals in order to keep her from being seen by the other foals. The room was filled with a variety of toys, a playpen, a changing table, and a large crib. Dashy was as content as could be. Occupying the center of the room, she played with herself with the Rack-e-Stack designed for the scattered plastic rings. She rubbed against the pole with her white diaper with pink leak guards running along the sides of the padding.
"Huhuffofooo d-d-dish w-wash aawwww dat I waned hehuh," she gurgled in the puddle of drool forming under her chin as she assumed a doggy-style position, diapered bottom raised up as her hooves did the work shoving the Rack-e-Stack into her soaked diaper. She was sooo close to cumming into her leaking Pampers when-
Gurgles"...hehehe dis is gunna be funs." She began to push, pushing the poll deep into her pussy as she grunted and pushed thick logs of poopy into her diaper, her diaper seat bulging outwards as the tapes of her diaper struggled to hold on. She felt soooo good playing with her new toys. She got even closer and closer to the edge when the tapes completely gave up, causing the diaper to fall onto the playmat with a loud sopping wet thud, pee leaking everywhere as cum leaked onto the ruined diaper. Her moan filled the small room.
All of the other caretakers looked at her with disgust.
Everyone except for Twilight Sparkle, who only looked at her with profound sadness as she slowly walked up to her, preparing to change her fourth diaper of the day.
"Oh, how I'll miss you, Dash."