Moonlight, Astronomical Twilight

Twilight was busy masturbating. She had been doing so ever since she woke up. Her mind flashed through various permutations of the dreams she'd had. Her fingers were jammed deep in her vag. Her thumb played with her clit. She couldn't stop thinking about that beautiful girl, that hellhound who'd changed her so.

Her eyes opened and she looked down at herself, still furiously masturbating. She wasn't a bimbo, but she was close to it. She wouldn't be out of place on any magazine for her curves, or her chest. She rivaled the queens for her body.
But that hellhound… Twilight groaned and moved her head back. For someone of her position, the idea of wanting to be dominated, to be seduced…

“Aah!” One hand passed over her breast. It felt like her sensitivity had dramatically increased! What else did this new body hide…?

Her mind went to another girl, another beautiful mare she loved more than even that dazzling hellhound. A short skinny mare with a pair of blue knockers… that could stand some improvement in a perfect world.

She lay back and braced her head against the side of the tub. She hadn't wanted to make a new mess of her sheets and had transferred to her castle bedroom tub a few hours ago. The bottom was coated in her juices. Soon would be a fresh batch…

“Twilight, you in here–?”

“Oh, Celestia!” She screamed as she heard the object of her affections.

Twilight’s member exploded. A massive explosion of fluids detonated and sent magic in all directions. Straight into a familiar mare who just walked in the door. She screamed, not in pain but in pleasure.

Rainbow Dash had been coming to see Twilight, they’d had plans to meet today. She’d just walked into the bathroom when the magic struck. Dash's clothes disintegrated, completely gone. Her breasts swelled to an enormous size. Her hips widened as her legs spread. She hit the wall, and her waist felt strange, crackling and stretching. “Ngh…” She moaned as her flesh hardened, reorienting itself. As she sat up, layers of flesh built onto her, leaving her quite musclebound. “What the…?”

Dash looked down at herself. Her bust had swollen to an enormous size, teardrop shapes nearly as large as her head. She cupped one of her breasts, her eyes wide. It jiggled tantalizingly, and she let it go. “I…I…”

Dash turned and looked in the mirror. A big, sleek, and powerful pegasus stared back at her. She felt her body, touching all of her transformations.

“Rainbow! I–” Twilight stammered.

Dash cupped her massive breasts, looking at the vast gulf between them. Her waist had drawn itself in, redistributing its mass to her hips and fattening it into an attractive form. She was curvy, much curvier than an athlete should be! Yet there was an exaggerated sleek Olympian symmetry to it. She felt powerful abs and thick thighs, long and sleek with muscular strength; not that she could see them past her new breasts. Her shoulders had broadened, giving her wide arms and thick biceps. Her hands traveled down, feeling herself up. Her body wasn't grotesque, it was… more something new. Her muscles were like marble, she was just so lustrous.

Then she felt a tingling, and something rising she didn't expect. Dash's eyes widened, and her hand wrapped around a cylinder between her legs—a thick, fleshy cylinder. Finally, Rainbow Dash looked at herself in the mirror again. “Whoa! What the fuck?” Between her legs was a cock the size of her favorite dildo. Massive weighty balls sat under it. As Twilight caught her breath with exhaustion, Dash turned toward her.

“Rainbow, I–”

Dash looked her up and down. Her mouth hung open, slowly drinking in the luscious details of Twilight's new body. Her eyes fixed first on Twilight's chest, then on her stomach. Her gaze moved to the mare's flanks and her ass, as well as her meaty thighs, before coming back to her face.

Dash's mouth slowly closed. “Oh… Twilight, you could've just asked!” she climbed into the tub with her and began stroking herself. She took to her new equipment with gusto, a determined expression on her face.

The muscular and athletic mare was the picture of attraction. Twilight stammered, blushing and mumbling. “Dash…” She finally managed to squeak out.

“What? I'm not doing anything.” The close quarters of the tub made the slick sound of her hand echo. Dash leered at her seductively.

“Rainbow– I'm sorry–”

Dash kept up her competitive face. “Someone dripping like that isn't about to say no.”

Twilight blinked. She looked down, still unused to the body before her, either Dash's or her own. Sure enough, her vagina was positively drooling. “I…”

“Yes or no?” Twilight looked up. Dash was hovering over her. She'd crept even closer. Her eyes went to Dash's chest, and finally her cock.

Dash had not thought her friend capable of this sensuality, or if she had pictured her like this for so long. It was plain as day to her, even as she crouched jerking herself off, Twilight had wanted this for ages. She didn't even know this level of transformation was possible…!

Twilight narrowed her gaze. Her horn arched with energy, a sure sign of arousal. Her nipples looked as hard as stone. She crawled over to Dash, unexpectedly dominant, and kissed her. She felt Rainbow's tall cock dig into her smooth Amazonian stomach. She felt slime spreading across it, the warm sensation of fluid leaving their bodies. “Yes…”

Doing “nothing” resulted in Dash exploding. A hot gout of baby battery struck Twilight's belly. She shrieked in shock. Dash groaned and shifted her hips forward. Blasts of goop ripped across her frame. Twilight stumbled back, leaning against the side of the tub. More cum splattered across Rainbow's body.

“Oh, holy shit–!” She stammered. Her eyes went wide. She kept ejaculating.

By the time she was done, the entire bottom of the tub was filled with Rainbow Dash's cum.

They looked at each other. Twilight was upon her in an instant. She slobbered her tongue across her face before she found her mouth. They made out furiously. Dash ran her hands around Twilight's naked back and pulled her close. Her erection rubbed against Twilight's thigh. Twilight's tongue went down into Dash's mouth and the rainbow mare gave a thrilled sound. Their bodies splashed in the copious fluids.

Finally, they broke, panting for breath. Dash grinned and looked down at their genitals. “You like dominant gals, don't you?”

Twilight panted, “I…”

“I may be pretty awesome, but I hope I can satisfy you.” She rolled them over. “Sweet Celestia if I'd known you wanted me this much I'd have picked you years ago! With this thing, I'm definitely gonna dick down some mares!”

“I didn't want to– Ah!-- I was so nervous!” Twilight arched her back. Rainbow was feeling up her chest like she owned it. She was a loyal and selfless mare, but that didn't mean she couldn't pretend to be the opposite in bed. She twisted Twilight's nipples and squeezed her tits.

“Oh my Celestia I love these things!” Rainbow gave her a rather sweet peck on the snout. She smiled warmly, even as she continued to grope the alicorn, “Well, no need to worry now. I'll take care of you.” Then she hesitated, and held her cock, “Assuming I can figure out how to work this thing.” Twilight grabbed it. Rainbow's penis immediately began to harden again. “A-a-ah!” She choked out.

With a shout, she shoved her cock forward. It slid between Twilight's breasts, and into her open mouth. “Mmf!” Twilight screamed.

“Oh my Celestia…” Dash moaned.

“Mmph… Mmph! Mmph!” Twilight squealed.

“Oh yeah,” Dash purred as she thrust, “Drink it down…”

Twilight kept suckling, kept giving Rainbow Dash's enormous and satisfying member the greatest blowjob she could. There was just so much of it. She gagged as it fed into her throat. Her eyes bulged as it went deeper and deeper inside.
Suddenly Dash’s eyes practically bulged out of her skull. She came. It was an explosion that filled up Twilight’s throat, and then her stomach immediately. Rainbow felt her mouth squeezing her cock like a vice. White hot fluid filled her up and bulged out her stomach. Rainbow tried to pull out, and succeeded, only to cover both of them in cum. When she finally stopped, they both looked like they were painted white.

“Oh… my…gosh…” Dash mumbled. They rolled over. “Ngh…” Dash groaned. “We need like a mat or something in here…” She held up an arm, her sky-blue skin stained with ivory fluid, “Ew…”

Twilight grabbed a towel and yanked it into the tub. “Here's something.”

The way Twilight moved, the way her breasts bounced and her muscles flexed made Dash aroused again. “So… so what do you think caused it?” She asked.

Twilight wiped cum off her skin as she thought. “I think somepony and I got linked in a dream. We were able to cast powerful spells over one another to make each other more appealing.”

“Then I'd love to meet who else has this sight on their bucket list,” Dash winked. “Ready for round two?”

"Maybe in a second..." Twilight leaned back.

As they lay there together, Dash had something on her mind. What about the mare Twilight had dreamed about?