My Existence, the Greatest Perversion.

Applejack and Rarity faced one another, the former with a look of determination and the latter with one of fear, while Pinkie, Rainbow Dash and Fluttershy backed away slowly. The two of them needed to talk to one another, and even Pinkie knew that this was not the time to talk.

“Why'd you run off, Rares?” Applejack asked, gazing at Rarity as she failed utterly to hide the quiver in her voice or the watering of her eyes.

Rarity simply lowered her head, sighing sadly as she did. “I doubt you'd understand,” she said. “I just didn't want to hurt you, and...”

“You leavin' like that hurt me plenty!” Applejack closed the distance, her lips flat and her eyes set, even as Rarity's demure white body shrunk back. “I love you, Rarity, and there's nothin' you can do that could possibly change that.” A blush spread across her face as her hard facade started to come undone. “... Even if that video I saw of you and the diamond dogs was a bit... er...” Applejack paused for a moment, as though unsure what to say. I don't even know what to think of it myself, she admitted quietly. Was it shameful? Embarrassing? Hot?

As if sensing what Applejack was thinking, Rarity simply shook her head and leaned forward to nuzzle the rough orange coat of her beloved. “I guess you knew what I was getting into, hey?” she said softly. “I know you probably think it dreadful, but I have my reasons, and-”

“I know,” Applejack softly whispered in Rarity's ear. Feeling Rarity tense up against her, Applejack continued. “You didn't do a great job of cleanin' out some o' your papers, and you know how I can be with doors.”

A soft, mirthless laugh escaped Rarity's lips as the two backed away from one another. “I'm not going to lie and say it's not enjoyable when I... feed,” she replied nervously, her deep blue eyes shifting awkwardly to avoid Applejack's pure, guileless emeralds, “but I do it because I have to. I need semen as surely as you need food and water.”

Pinkie might have known how to keep quiet, but Rarity's words ignited a curiosity in Rainbow Dash that just wouldn't go away. “Wait,” the pegasus suddenly blurted out, raising a hoof to get the lovebirds' attention even as Pinkie and Fluttershy glared at her. “I've seen you eat a bunch of times, and you don't just toss up right after, so what happens to that?”

This time, it was Rarity's turn to blush. “Yes, about that...” She let out a cough. “Since I don't have an excretory system and normal food isn't compatible with me, well... Let's just say I've been known to spend a bit extra time... powdering my nose... After holding it in public.”

Every pony there took a moment to digest Rarity's statement. Then, they all started turning a bit green, imagining Rarity with her muzzle over a toilet, retching out every meal they'd ever had together as her body rebelled against it.

Fluttershy was the first to speak up, her soft, wispy voice bleeding the sincerity she felt. “I'm sorry,” she said. “It must have been really hard trying to look normal.

“Yeah, totally!” Pinkie chirped, running over and giving the alabaster pony a tight hug. “I can't imagine how bad it must have been with all those cupcakes I made for you!”

Rarity's blush only intensified. “R-really, it's fine...”

“Naw, it ain't,” Applejack chimed in, her eyes trembling as she held back the tears. “I should've seen something was wrong, and you should have been able to trust me enough to tell me.

At that, the mood among the five of them darkened. “Tell you what?” Rarity asked. “I can't exactly be blamed for not expecting ponies to understand my... Condition.”

“Yeah, she's kinda got you there, AJ,” Rainbow agreed.

“Still,” Applejack insisted, “You had to have known I'd never leave you....” She flinched a bit at that statement as the conversation with Fluttershy on the train came back to mind. I would have stayed with her... Would I?

Her own eyes starting to well up, Rarity shook her head. “That's why I had to be the one to leave!” she exclaimed. “You deserve better than this, Applejack! Better than me!”

With that, Rarity turned around and ran off, crying openly as she ran deeper into the alley before turning a corner and going out of sight.

“Hey, hold up!” Applejack shouted at the fleeing purple mane before giving chase, Fluttershy and Pinkie at her sides while Rainbow flew past them.

–

Urban sprawl, as it turned out, proved quite easy to get lost in. Many twists and turns provided by tightly packed buildings and crowds of ponies made it hard for the four of them to track Rarity, with even Rainbow and Fluttershy unable to really see them from over the crowded urban landscape.

Eventually, Applejack had to accept that she had lost Rarity. Again. Stopping in front of a tall apartment building, Applejack sighed and fell to her rump, trying to catch her breath. Since when did Rarity of all ponies get so athletic?

The group gathered around Applejack and all took turns patting her shoulders, Pinkie smiling softly as she did. “You'll get her back!” the pink pony assured her. “We just gotta keep trying!”

“Yeah!” Rainbow Dash agreed. “She can't resist you forever!”

Applejack looked down at herself, unconvinced. “I ain't worried about her not wanting to be with me anymore,” she said glumly, sniffling as long-repressed tears started falling from her eyes. “I'm worried about convincing her that I can live with what she is, what she's doing...”

The group was rather quiet for a moment, the four of them pondering Applejack's words. Obviously, Rarity not feeding was out of the question, and Ponyville provided very few stallions, fewer still who weren't already hitched up. Thus, this was a perfect place for the former fashion designer. It was also not exactly a life for ponies in a steady relationship, what with all the filming. Thus, it would be a challenge convincing Rarity that, no, she wasn't going to burden Applejack.

“Um...” Applejack, Pinkie and Ranbow all turned to face Fluttershy, who was hovering just above the ground and trying to hide behind her mane again. “I was thinking you could, um...” She squeaked and turned her head away, blushing.

“What could I do, Fluttershy!?” Applejack exclaimed desperately, looking up at the yellow mare intently.

Swallowing hard, Fluttershy willed the rest of her thought out of her trembling lips. “Y-you could... D-do a porn film yourself...”

The other three simply looked at Fluttershy, blinking as they stared in shock.

“Where's Fluttershy...” Pinkie began.

“...And what have you done with her?” Rainbow finished.

Applejack considered Fluttershy's idea for a moment. It was preposterous, foolish, and would almost certainly cost Applejack most of her reputation.

It was also a genius way to both keep Rarity in a place she wouldn't be able to run from and show her that Applejack would do anything to be with her.

Slowly nodding, Applejack flashed a smile at her shy friend. “That sounds like an idea.”