Rainbow Dash hadn’t even noticed the growth initially, partying her night away within the depths of the nightclub. It had been subtle first, her drink tasting slightly off (Though she chalked that up to being buzzed). Then her clothes started tightening, stretching as her curves began to bloat outward. It was several minutes after consuming her drink that the blue mare realised something was off. Her breasts took far longer to stop shaking than usual, especially with a tank top on. In reality, they had more than tripled in size, nearing that of her head. Her butt had soon followed behind, her widening hips giving her swelling asscheeks all the more room to grow and bounce as her thickening thighs tore through her shorts.
 
 
She finally decided it was worth slowing down and investigating when she felt her underwear riding up, reaching back to grab one of the straps, she let out a gasp to find that even the slightest tug on the fabric was making the wedgie worse. Turning to try and get a look, she realized that not only had the growth she ignored as an illusion of the mind shredded her clothing, but it had turned her otherwise normal underwear into a wedgie-inducing thong!
 
 
Even as she attempted to remove it, her chest and rear kept swelling. Eventually, she gave up around the time that her hips, which were more than twice the width of her body, snapped through the offending garment. The bouncing of her chest seemed to have been joined by a heavy sloshing sensation. Realizing this, on top of it just occurring to her she was nude, the cyan mare made a beeline for the bathroom, moaning as her fattened breasts and widened rear squish against the doorframe. She didn’t even notice her ears brushing against the top.
 
Rainbow looked at herself in the mirror, she was enormous! Her breasts alone were probably well outside the standard alphabet of bra sizes, slightly larger than beach balls…and she was still growing! She pressed her hands into her breasts, gasping in worry as she noticed milk of all things leaking out of her thickening nipples. Looking at her reflection, she realized just how tall she’d gotten. She was nearly seven feet…she could last recall she stopped growing taller naturally when she was about 5’4”… 
“Wow…I’m not sure what’s worse; the fact that this is happening, or the fact that I’m enjoying it more and more the bigger I get…” Pondering this she hefts one of her huge nipples to her mouth, her jaw hardly able to wrap around the thing as it gushed. Closing her lips around it, she gulped.
 
 
The effect was almost immediate. Pleasure shot through her as her body surged in size. She wasn’t even eye-level with the top of the mirror. Crouching down only slightly, and feeling her breasts and ass press into the floor due to their sheer size. She looked over her swollen sweaty naked body, and the gallons of milk pouring out of her nipples… And grinned. “Y’know what? To Tartarus with being the fastest in Equestria, I reckon I can settle with being the sexiest…” With that, she turned to the bathroom door, pushing through it with ease. She watched the crowd turn to silent stares as the ten foot tall hyper-hourglass-shaped mare walked into the middle of the dance floor, a cocky grin on her face. “Well everypony? Don’t let my appearance stop you from partying! Free milk for all!” A drunken cheer rose up from the crowd as the music went into full swing again.
 
The rest of the night was filled with the sounds of moaning and stretching or tearing clothing as Dash’s unexpectedly productive chest fed the club goers for the rest of the night…