No, Seriously. She Can't.
Author's Note
If you're considering taking this fanfiction seriously... just don't. Don't do it. Don't. You. Do. It.
This story is meant to be ridiculous, just like most of my other one-shots. Don't try to see it as anything beyond that, because you'll be disappointed. And maybe confused. 
No, Seriously. She Can't.
“Rarity, that dress is going to blind ponies,” Rainbow said flatly, squinting against the reflections coming of of Rarity’s heavily-sequined dress. “Just because the Breezies are gone doesn’t mean anypony else wants you wearing stuff like that.”
“But Rainbow,” Rarity protested. “Sequins are so in right now! If I want to make a name for myself, I have to be seen as keeping up with the times!” She spotted Applejack walking down main street and grabbed her. “Applejack, you like my dress, don’t you? Even a common farm worker has to be able to appreciate this level of beauty!” Applejack chose to ignore the ‘common farm worker’ comment.
“Uh… it’s mighty shiny, Rarity,” she said with a nervous laugh.
“See?” Rarity said triumphantly.
“It’s too shiny,” Rainbow insisted. “That’s my whole point!”
“If it makes Rarity happy, we may as well leave it, RD,” Applejack sighed. “She’s not hurtin’ nopony.”
“What’s going on?” Twilight asked, seeing the small gathering and trotting over with Spike on her back. He gazed wide-eyed at Rarity, ignoring the stinging sensation of the burning light on his retinas.
“Rainbow Dash is insulting my masterpiece!” Rarity whined, flipping her hair in indignation. Rainbow rolled her eyes.
“If the whole point of dressing up is basically to get stallions to look at you, burning their eyes out is NOT the correct way to go about it,” Rainbow huffed.
“How would you know how stallions think, Rainbow Dash?” Rarity demanded.
“It’s how anypony would think!” Rainbow yelled, just a touch too quickly.
“Some element of loyalty you are,” Rarity sniffed, tearing up dramatically. “You’re supposed to support your friends! You’d be better off as the element of brutal uncensored honesty!”
“Hay!” Applejack snapped. “Honesty’s my department!”
The other three mares gave pointed looks that clearly were meant to bring up memories of the cherry orchard incident, the second Flim and Flam incident, and several other instances where AJ hadn’t quite lived up to her element.
“Keep telling yourself that, AJ,” Rainbow said. “But you can keep it, cuz’ I’m not honest, like at all.”
“I don’t know, Dash,” Twilight said with a shrug. “You may not be quite as tactful with your honesty as AJ is, but you don’t hold yourself back when it comes to telling the truth as you see it.”
“Hay!”
“Is for horses!” Spike exclaimed. “Oh, wait.”
“No, really. No way I could even kind of be sort of close to honesty,” Rainbow insisted uncomfortably.
“And why is that?”
“... Oh, look at the time! Gotta dash. Weather duty calling and all that,” Rainbow said quickly, and launched into the air at almost Sonic Rainboom speeds.
“Ooh, secrets!” Rarity said with a delighted clapping of her hooves. “We simply must find out whatever juicy gossip she’s hiding from us!”
“I don’t know Rarity. Wouldn’t it be better to let her open up when she feels like talking? I mean, if that’s okay with you…” Fluttershy said from somewhere over Rarity’s shoulder, causing the seamstress to jump violently.
“Oh, goodness!”
“Oh my, I’m sorry, Rarity,” Fluttershy exclaimed. “I certainly didn’t mean to startle you.”
“Don’t fret over it,” Rarity said, her heart calming a bit. “My dear, how long have you been standing there?”
“Um, the whole time.”
“Why didn’t you say anything?”
“I did.”
“Talk louder, sugarcube,” Applejack said, shaking her head amusedly. “Nopony’s gonna hear ya, otherwise.”
“Oh, right.”
“Anyway, back to your question, darling,” Rarity said. “If we wait for Rainbow Dash to open up, we’ll all be dead long before she says anything.”
“What if it’s not something that we need to know?” Applejack asked. “Ponies’re allowed secrets, y’know.”
“I think Rarity’s right,” Twilight said. “We’ve all seen what keeping secrets can do to friends.” She looked at Rarity and Fluttershy. “As much as Rainbow doesn’t like to talk about personal things, I’m sure we’ll all be better off when everything’s out in the open.”
“So what do you suggest, dear? There’s no way we’d be able to chase her down once she knows we’re on to her,” Rarity pointed out.
“I can think of somepony who can!” Spike exclaimed, raising a hand like he was reliving his young(er) days of being forced into playing school with Twilight.
“Hey, Pinkie!” Twilight called as they walked into Sugarcube Corner. Pinkie poked her head out of the kitchen.
“Yes, Twilight?” Pinkie poked her head out of the kitchen, a tray of freshly baked cupcakes resting on the top of her mane.
“Any chance you’d be up to chasing down Rainbow Dash for us?” Rarity asked pleadingly. “We think the daredevil is hiding something from us, and that simply won’t do!”
“Secrets!? But we all collectively Pinkie Promised not to keep secrets anymore because it damages friendships! Forever! NOPONY BREAKS A PINKIE PROMISE!” Before any of them had the chance to blink, Pinkie Pie was standing in front of them with a smug look on her face, a huge butterfly net over her shoulder and a confused and disoriented Rainbow Dash trapped in its restricting depths.
“Well that was fast,” Applejack commented.
“Hey, what gives!?” Rainbow complained, coming to her senses.
“TELL US YOUR SECRET OR I WILL SHOVE YOU INTO A DRESS SO POOFY PINKIE’S MANE WOULD WILT IN SHAME!” Rarity shrieked. She coughed delicately. “I mean, if you would be so kind as to stop shutting us out, we’ll all be here for you, darling.” All those present, excluding Pinkie, stared at her mutely. She, meanwhile, just stood there pleasantly waiting for her friends to interrogate Rainbow as promised.
“What are you guys even talking about!?” Rainbow exclaimed, struggling to claw her way out of the soulless pit of the net.
“Why ya been actin’ so weird?” Applejack inquired.
“What do you mean, weird?” Rainbow demanded.
“You’ve been quite defensive ever since commenting on my dress earlier,” Rarity said. “We think you’re hiding something important from us. We all promised-”
“PINKIE promised,” Pinkie interrupted.
“Ah, yes. Pinkie promised. We all Pinkie promised that we wouldn’t keep secrets from each other.”
“I’m not keeping a secret!” Rainbow yelled.
“Liar,” Applejack accused, raising an eyebrow. “Ah may have a terrible poker face, RD, but Ah can read ponies like I can read a… well, like Twilight can read a book.”
“And you did seem a bit too defensive earlier not to be hiding something. Why else would you be so insistent that you’d make a terrible Element of Honesty?”
“Because… um… the orange would clash with my complexion?”
“Actually, dear, orange and blue are complementary. Besides, you already have orange in your mane!” Rarity pointed out.
“Oh. Right. Darn.”
“So what is it REALLY, Rainbow Dash!?” Pinkie said, getting right into Rainbow’s face, causing Rainbow to cease the struggle with the net.
“Seriously, Pinkie?” Rainbow asked, raising an eyebrow meaningfully. The look did not go unnoticed by the others, who all immediately rounded on Pinkie.
“Do you know what she’s hiding!?” Rarity gasped dramatically.
“Hmmmmmmmmm……” Pinkie thought long and hard, screwing up her face in concentration. “Well, probably. Dashie tells me everything! But I dunno which super-duper secret Dashie has that you all don’t know!”
“It’s a super-duper secret that’s better off staying that way!” Rainbow exclaimed. “Lemme go!”
“Tell us the secret, or no frosting on your cupcakes for a week!” Pinkie threatened.
“Pinkie, come here,” Rainbow huffed, beckoning Pinkie closer. She complied, and Rainbow whispered something in her ear that none of the others could hear.
“Oooooohhhh,” Pinkie said, nodding in understanding. “You mean they don’t know about that!?”
Rainbow shook her head.
“So that’s why we…?”
“Yup.”
“And why everypony says…”
“Yup.”
“Well that’s silly! We should totally tell them so we can have a ‘Everypony Knows Rainbow is Really a Stallion and is My Coltfriend Party’!”
“PINKIE!”
“Say whut now?” Applejack asked, blinking several times.
“Dang it! I was waiting on the reveal for another year so it’d be the longest-running prank I’ve ever pulled, Pinkie! All this time wasted!”
“Whoops. Sorry. Forgive me?” Pinkie pouted, sticking her bottom lip out sadly.
“I never could stay mad at that face,” Rainbow chuckled, shaking his head. “Wanna let me outta the net? Also make sure Rarity’s still breathing. I think you broke her. And maybe everypony else.”
