Derpy flew aimlessly through the sky, malicious thoughts on her mind. She’d ran her usual errands earlier: bought some apples from the Apples (mentioning that joke to them for the fiftieth time), got her special muffin order from Sugarcube Corner, and offered help to everyone she thought needed it (as usual, none said yes). Though now that she was all alone, this facade disappeared and was replaced with a devilish desire for torment. A devious grin slowly affixed to her face when she noticed a familiar pony up ahead. The cyan pegasus was busy clearing the sky and hadn’t noticed her grey companion approach her until she was barely a few feet from her.
“Sweet Celestia, Derpy!” Rainbow Dash exclaimed as she turned to face her friend. “Don’t scare me like that!”
“Hehe, sorry,” Derpy replied, grinning innocently. “So, whatcha doin’? Anything I can help with?”
“Just clearing away these annoying clouds,” Rainbow Dash said. “I’m almost done though, thank Celestia.” She hated having to work, especially long hours.
“Oh, ok! Just let me know when you’re done, I have a surprise for you.” Derpy said this with an almost childish grin on her face.
“Uh… ok.” Derpy barely heard Rainbow’s reply as she descended into a heavily forested area nearby. She wandered for a few minutes, the evil grin appearing once again on her face. After a bit of searching, she came across a rather large tree that looked like it was relatively weak. She bucked it forcefully a few times on the base of its trunk until it looked as if one more kick could send it to the ground. She then flew to the top of a nearby tree and waited for her rainbow-maned companion to join her. She glanced once at her bubble-emblazoned flank. This, she thought to herself, is going to be fun.
* * *
Many thoughts ran through Rainbow Dash’s mind as she kicked away the last few pesky clouds. It wasn’t abnormal for Derpy to give her gifts every once in a while, but the secrecy of this particular gift boggled her mind. She didn’t contemplate it too much, and along with the destruction of the final cloud, her suspicion subsided. She made her way down to the forest and scanned the area for the googly-eyed pony. Noticing her sitting on top of one of the trees (which was odd, even for her), she flew over to her. “Hey Derpy,” she said. The grey pony turned toward the sound of her name and greeted Rainbow with a delighted smile. “You said you had a surprise, or something, for me?”
“Oh, yeah!” Derpy replied, as if she forgot completely why she wanted to meet with her friend. She tended to do that a lot. “Follow me.”
The nature of this gift grew much more unusual as they flew through the forest. What could she have for me here? Rainbow Dash wondered. She didn’t get to contemplate it long before they came to an abrupt stop. “Wait here,” Derpy said, pointing to specific area on the ground. Rainbow obeyed, awaiting whatever Derpy had for her. As the pegasus flew away, Rainbow was left with her surroundings. Amid the thick foliage were a few small animals scurrying about, but there was nothing noteworthy. What she did notice though, was a particularly large tree behind her that looked as if it was greatly decayed. “Close your eyes!” she heard from a distance. She sighed and obeyed, this time an eager smile slowly forming on her face.
Derpy returned, but didn’t have anything with her. Instead she flew at a rate that would impress the Wonderbolts, tightly rounding the corner of the damaged tree. Her hip collided with the tree with enough force to cause it to slowly topple over in Rainbow’s direction. The blue pony turned to inspect the loud noise, but only had time to gasp loudly before she was crushed under its weight. “Oops, my bad.” Derpy said, guiltily. She flew over to the fallen tree and, with admirable strength, lifted it off of a now paper-thin Rainbow Dash’s body.
“Derpy!” Rainbow yelled, angrily. The way she looked made Derpy giggle lightly, but she stopped when she noticed the rage in her victim’s face.
“Sorry, but you look kinda funny,” Derpy responded. She received only a look of pure frustration. “Okay, okay, I can fix this.” She peeled Rainbow Dash off of the ground and carried her into the sky. After flying away for a few minutes through the clear sky, she came across an area that hadn’t been cleared yet. Plopping the pancake of a pony on one of the clouds, she flew to the ground, returning with a simple bike pump. “Here we go!” she exclaimed in glee.
“Derpy, I don’t know if this is a goo- mmph!” Rainbow was interrupted by the forcing of the hose end into her mouth. Without hesitation, Derpy began pumping, slowly filling Rainbow to her typical proportions. As she reached her usual size, she gave Derpy a grateful look, although it faded quickly when she realized she was still growing. Her expression grew worried and she waved at Derpy to stop, but she wasn’t letting up anytime soon.
“No, no, you’re certainly not full yet,” Derpy said, as the malevolent grin that graced her face several times before reappeared. The look on Rainbow Dash’s face changed from worry to panic as Derpy sped up her pump rate. Her belly grew downward until her hooves barely graced the cloud below her. She looked around rapidly, hoping for someone to come and help her, but it was obvious that Derpy took the necessary precautions to keep her concealed.
Eventually, Rainbow’s distended belly lifted her hooves entirely off the ground. Her hooves were also growing, shaping into thick tubes on her swollen body. As she was filled more and more by her equine friend, her skin gained the consistency of rubber, stretching outward noisily and reflecting the light from the sun overhead.
Derpy couldn’t help but look on with sinister glee as the cerulean pegasus expanded to almost unthinkable dimensions. Her face turned from its initial panic to one of great distress as her extremities were forced outward on either side. Her wings also ballooned, filling up and shining as did the rest of her body. The pressure grew substantial as her overfilled limbs began to sink into her ballooning body. Her rump protruded behind her body, filling with air beyond her control.
Rainbow’s ever-expanding body shone brightly enough so that her fur was indistinguishable from her skin, which was becoming translucent. All limbs on either side morphed into small, round stumps inside large, circular balloons. Her wings grew as vastly as the rest of her body, which was now hardly unlike a blimp.
Derpy paused for a moment to examine her handiwork. She flew over and poked her hoof into Rainbow’s inflated abdomen, much to her dismay. It sank a few inches, then snapped back quickly as it was removed. “No, not quite,” Derpy said to herself. She made her way back over to the pump and winked at Rainbow Dash before beginning to thrust the handle again.
Rainbow eventually stopped resisting, awaiting her impending doom. Her head sunk into her body as she continued to expand outward, holding highly impressive amounts of air. Her limbs and rump at this point had blended in with the rest of her body. Any passer-by wouldn’t even recognize Rainbow as a pony at this point, just a surprisingly (and probably unnecessarily) large balloon.
Derpy stopped again and flew over her air-filled creation. She landed next to one of her nearly transparent wings, causing Rainbow's body to utter a loud creak. The size comparison was remarkable, as Derpy could’ve fit her entire body on just one of her feathers. Walking around a few paces, Derpy seemed content with the pressure of her new balloon. For fun, she pranced around and even jumped a few times; the pained grunts coming from Rainbow’s concealed head pleased her greatly.
She flew over to whatever of Rainbow’s head was still visible and held out a small object, which Rainbow Dash quickly noticed was a cork. She yanked the hose out of her mouth and plugged the hole again, so as not to waste this beautiful piece of artwork she created. She then flew under Rainbow and lifted her up by the belly, which, due to her near-weightlessness, required little effort. She held the pegasus above her head, reached back as far as she could, and hurled her toward Cloudsdale. She flew easily and almost comically toward the highly populous city, spinning and twirling helplessly.
Derpy, feeling content in her work, flew over toward Ponyville, eager to get home and enjoy those muffins she bought earlier. As she flew back, though, she noticed another friendly face wandering through the main square. She looked very confused and worried and…. helpless.
“Hey, Fluttershy!” she yelled as she flew toward the yellow pegasus. “Whatcha doin’? Anything I can help with?”
