Turn on and Shrink Down (Twilight, Rainbow Dash, Shrinking, Masturbation)
"Geez, Twi!" said Rainbow Dash, rubbing at her dazzled eyes with balled hands. "Did you, like, actually have to blast me in the face?"
"I didn't mean to!" said Twilight, rushing over to Dash's side. "You just kicked open the door, and I turned my head... I was trying to cast it on this thing." She gestured to an old dressmaking dummy, something she'd saved from the garbage when Rarity had been ready to replace it. The goofy smile, drawn in purple marker, was her own addition. She'd been focusing intently on the dummy, ready to enchant it, when RD had kicked open the door of the Golden Oak library in her usual manner.
"Uh, okay," said Rainbow Dash. "So am I gonna be okay? I'm not, like, gonna go blind or something?"
"No!" said Twilight. "I mean, the spell is a work in progress, so I can't one hundred percent guarantee that any given effect will or won't-"
"Well," said Rainbow Dash, "If I do go blind, will you be able to fix it?"
"Oh, definitely!" said Twilight. "I always keep careful notes on my spellcraft. Researching a counterspell won't take more than a few hours at most."
"Okay. Cool," said Rainbow Dash. She pulled a chair out from Twilight's dinner table, turned it, and sat facing Twilight. "So what did you cast on me?"
Twilight turned her eyes away from Dash. "Well, it's not really... I, uh..." She sighed. "Magical ethics dictate that subjects of enchantments have a right to know what spells have been cast on them," she said, as if reciting it from a book. "I've been experimenting with analog enchantments. Uh, for example, you could have... an enchanted lamp that gets brighter as there's less and less natural light in the room."
"The spell I was trying to cast on the dummy," Twilight went on, "Was intended to make it smaller. And the trigger for that was..." Twilight exhaled a long breath. "Uh, the thing is, I've also been experimenting with magic that concerns sex and sexual health-" Twilight saw the look of concern of RD's face and raised her hands in front of her. "-Which is an important and valid branch of thaumaturgy, responsible for many conveniences we enjoy today..."
"Can you get to the point?" said Dash.
Twilight sighed. "The spell makes the target smaller the more... sexually aroused I get."
Rainbow Dash's face twisted into a confused grimace. "Why?"
"I was just trying to have a little fun. Alone! Behind a locked door."
"Was it locked?" said Dash. "I never check."
Twilight groaned. "Well, I'll work out a counterspell. Just... stick around, I guess."
"And try not to make you horny? Or I'll start... shrinking?"
"...Yeah."
"All right," said Rainbow Dash. "Get to work."
Twilight took a seat at her desk and got to work, looking over her notes and occasionally making a mark on a blank page. Her work started smoothly enough, but it only took a few minutes before she heard an irritable foot-tapping from Dash's direction. She leaned over her desk and did her best to ignore it, but soon RD started sighing as well. Clearly, Twilight should have known better than to expect Dash to sit still and be quiet.
"Yo, Twi," said Dash.
Twilight frowned and set down her quill. Crafting a counterspell was precise work, and there was no hope of doing it while she was distracted. "Yes?" She said, without turning around.
"So how small would I get exactly?"
"Uh..." Twilight felt herself starting to sweat. Don't imagine it...
"And how fast would I shrink? If you got turned of, would my head, like, come up to your boobs? Or to your waist? Or would I, like, get as small as Applejack was that one time with the Poison Joke?"
Twilight whimpered. There was no avoiding it now; imagining Rainbow Dash getting smaller was making her horny. Twilight had been a microphile for as long as she could remember. The spell she'd cast on Dash had been intended solely for her own gratification - to watch things get smaller while she touched herself. To let her arousal exert power over the world around her. But it wasn't a dressmaking dummy that was under her power now - it was Rainbow Dash, the bold, beautiful athlete. And Dash was forcing Twilight to think about her fantasy scenario coming true.
"Whoa!" said Dash, as her perspective got lower by a couple of inches. She assumed she was falling, and clutched the sides of the chair she was sitting in. Twilight didn't turn to look at her - she knew that seeing Dash shrink would only make her hornier. She looked back at her notes, trying to focus again, but the tingle of arousal in her core was still growing stronger.
Dash shrank again, losing another few inches, and this time she understood what was happening to her. Her shirt hung loosely on her torso, and her ass-hugging jeans were suddenly spacious and baggy. "What the hay, Twilight!" she said. "Are you getting horned up over there?"
Twilight gritted her teeth. She just had to focus on her work, she told herself. She just had to immerse herself in spellcraft and forget about what was happening behind her. Only - she was awful at focusing when she was horny. She'd never gotten good at it. Her usual strategy was to quickly masturbate and get back to work, but if she did that, Dash would get so small she would fit on Twilight's fingertip...
And of course that mental image only made things worse. Dash shrank again, now a full foot shorter than her original height, and she stood from her chair and stormed over to Twilight. "Hey, Twilight, can you cool it?" She grabbed Twilight's shoulder, and Twilight reflexively turned her head to look.
And behind her, she saw Rainbow Dash, her clothes hanging loose, her eyes barely level with Twilight's even though Twilight was seated. And Twilight's pussy surged with arousal at the sight. Seeing Rainbow Dash like this - and knowing that her pussy had the power to make her friend smaller and smaller - was the hottest thing Twilight could imagine. Rainbow Dash started shrinking nonstop, losing a couple inches every second, and she tripped and fell, succumbing to vertigo and tripping over her loose trouser legs.
Twilight gave in. She was only going to get hornier now; getting herself off was the only way she'd regain her focus. She jammed her hand down her skirt and began to finger her slit, watching the one-foot-tall Rainbow Dash squirm underneath her own fallen t-shirt. When the pegasus burst free, she flapped her wings and flew to the level of Twilight's breasts. "What the hay are you doing?" she demanded. The tiny, high-pitched squeak of her voice only drove Twilight closer to climax, and she rubbed feverishly at her clit as she stared at Rainbow Dash, hovering in front of her, tiny and still getting smaller.
Dash was gripped by vertigo as she shrank to one inch in the space of an instant. All the walls of the room seemed to recede from her at dizzying speed, and Twilight's body became a mountain before her eyes. Totally disoriented, Dash went into a nosedive, falling down, down, past the endless lavender expanse of Twilight's T-shirt, down into the space between Twilight's crotch and the hand she was using to touch herself.
And Twilight felt it. She knew the tiny, squirming form caught between her pussy lips was her friend Rainbow Dash. She knew that the tiny, flitting movements on her slit were Dash's struggles as she flailed her nectar-soaked body in confusion and helpless anger. Twilight's pussy was surrounding Dash, and it still had the power to make her smaller and smaller and -
Pussy juice washed over Rainbow Dash as Twilight came, and the muscles underneath her tensed and released with the force of an earthquake. A deafening cry shook her eardrums, and she stared up at Twilight's face, which grew larger and larger as her climax went on. Twilight's body was like a landscape to Rainbow Dash now, every gentle curve of her body a mountain. And the mountains quaked in climax, long and hard, before finally falling still.
Twilight blew out a quick, short breath and pulled her hand out of her skirt, leaving Dash in darkness, her gnat-sized body still lying on Twilight's dripping slit. "All right, Dash" she said, "I'll get back to work, and I'll have that counterspell for you in a jiffy. I can barely feel you down there now, but just in case..." she giggled, "Try not to move around too much, okay?"
Author's Note
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