Butter and blood
Fluttershy sat in her home, drinking tea and eating a warm piece of toast with butter and apple jam on it. She loved breakfast. Then again, she loved pretty much everything. As long as it wasn't scary. Like the toaster when the toast popped up. She finished the crunchy bread with a smile and polished off her tea. It was time to feed the chickens.
Humming happily, the yellow pegasus trotted to her shed where she kept the chicken feed. She placed a hoof on the door handle and pulled it open with a soft creak. The sight inside elicited a gasp from her. All of the items that had been stored on shelves had fallen. Broken glass jars that had held treats for her animals littered the floor. Small garden tools and spilled bags of fertilizer and seed were scattered about. Eyes wide, she surveyed the disaster and knew exactly what happened. She had seen a stray cat prowling the area lately, and had yet to deal with him. He must have chased some smaller animal into the shed and caused this utter catastrophe.
She huffed angrily, but, just as always, took her anger and buried it deep inside herself. As she did, she felt something inside break. It wasn't physical, but it was unpleasant. Her heart began racing, but she couldn't understand why. Her breaths came quickly, with involuntary growls accompanying each exhale. Her mind flooded with thoughts of violence. The hair on her back stood on end, a subtle warning to any who might see it. Her vision took on a red tint and finally, she screamed. A rage-filled roar that would send chills down the spines of those near enough to hear it. In her mind, anyway. In reality, it was a soft high-pitched squeal.
And then Fluttershy as Equestria knew her was dead. In her place, stood a being of pure, unfettered fury. She turned away from her shed and her eyes looked toward Ponyville. She didn't know or care about why or how, but she knew they would pay. Her wrath would be indiscriminate, directed at any and all who dared to enter her field of vision. The fire burning inside her was one that could only be extinguished by blood and tears. She began to move, now on a warpath, stomping with light hooffalls that sent up little clouds of dust from the road.
There were no ponies on the road before Ponyville, as usual, so by the time she reached the town, none had yet fallen under her mercilessness. Then she saw a stallion coming toward her on the road. The other Fluttershy would have recognized him as Caramel. This Fluttershy did not care. He had a book clutched to his chest with one hoof. With a single purpose in mind, she fixed him with a withering stare and turned herself toward him. Some part in the back of her mind thought oh, you poor, poor stallion.
"Good morning, Fluttershy!" he said cheerfully as she approached him. There were no words to reply with, as only the complete annihilation of this individual would suffice. As she neared him, he tried to turn away to avoid colliding with her, but she turned with him, marching forward with an unstoppable mechanical gait. Time seemed to slow as her body collided with his, bumping him aside, causing his book to fall from his grasp. It landed on the road with a dramatic thud.
"Whoops. My apologies," he said.
And then she continued on without apologizing or stopping to pick up his book. Her heart hammered in her chest and she felt a surge of adrenaline, the raging inferno dying down just a little. Yes... yes! I need more, she thought as she continued into town.
From somewhere behind her, came a faint "Have a nice day!" And then he was gone, behind her both literally and figuratively as she set her sights on the rest of Ponyville.
Before the main part of town was the bridge over Ponyville Creek. And before that was a house that was built directly between her and said bridge. The road gently curved around it, as if literally bending to the will of a mere structure. Old Fluttershy would have made excuses. I prefer the scenic route anyway, or if a pony wants to live there, that's their right. What a shame that Current Fluttershy was not given to making such concessions.
She did take the road around the house, but not to yield to it. She was circling it. A predator stalking injured prey. A preemptive victory lap celebrating its impending demolition. With a wolfish grin, she trotted up to the offending dwelling and looked it up and down, sizing it up. Knowing it would be the last time she ever saw it, she said a sarcastic 'goodbye' under her breath and snickered as she turned around. She leaned her weight onto her forehooves and brought her rear hooves in close to her body, coiled springs ready to be released. Then, with the might of a thousand butterflies, she kicked the house. She didn't even bother looking back as she walked away.
"Huh?" came a mare's voice from behind her. "Oh, hi, Fluttershy!"
The yellow pegasus was certain it was some kind of anger-induced hallucination, as she was sure the building (and maybe everything a half mile beyond) was reduced to rubble. She just kept walking, not even giving it a second glance. It was done, and there was more havoc to cause.
Over the bridge, Fluttershy saw the marketplace on her left. It was busy, and there were plenty of potential victims in that direction. She smiled wickedly as she proceeded toward it. She knew what to do. Twisting her face into a horrifying scowl that could wilt daisies, she advanced on the unsuspecting ponies. They say 'if looks could kill...' and hers, she was sure, could. Smiling, crying, and being afraid were pretty much all she knew how to do, however, so her current face was actually just her normal smile except without the happy thoughts and silent well-wishing that usually came with it. Needless to say, she left a trail of agony in her wake as she went to the carrot stand.
The carrot pony, whose name presently did not matter, was turned away from the counter doing some kind of busywork with the bins of carrots in the back. Next to a display of carrot bundles, there was a bell on the counter meant to let customers get her attention. A terrifying idea came to Fluttershy's mind. Well, terrifying for the carrot pony, not for Fluttershy. She took a bundle of carrots and left 5 bits on the counter (four for the carrots plus one as a tip), and didn't even ring the bell or say 'good morning'. She was sure it would leave the poor carrot stand owner confused, wondering who bought carrots while she wasn't looking. It was certain to cause her world to come crashing down around her.
Fluttershy briefly considered throwing the carrots on the ground and stomping them to mush, but even in her present state, there was one creature she truly feared; Angel Bunny without his carrots. The fearful thought cut through her rage like a hot knife through butter and manifested itself as a shudder. It no longer mattered, however. She had the carrots. She was safe. Unlike Ponyville.
Next on her list of things to irreparably demolish was whatever was in front of her. It happened to be Carousel Boutique. She made for the dress shop, fiery fury burning anew, and walked right in without knocking or announcing herself.
"I don't like the dresses here!" she yelled, just above a whisper.
Rarity, who was organizing some clothing on a rack, heard this. "You know, I agree. I haven't had time to keep up with the latest fashions in between teaching and running my other shops. I really should find the time to..." she said as she turned, noticing whoever had said it had already left. She shrugged and turned back to the rack.
Fluttershy marched. Driven by her bloodlust, her insatiable thirst for carnage and mayhem, she marched. On to the next victim, pony or not. She was ready for anyth-
"Hi Fluttershy!" an excited voice said from directly behind her. And she barely even jumped. Ha. She wheeled on the the perpetrator. It was Pinkie Pie. "Hey, so tomorrow is the 16th monthaversary of when Thunderlane found that trophy he lost and I wnnff trr frrw mm prrtrr frr hrm." Fluttershy had jammed a hoof into the pink mare's mouth, but she just kept talking. It was time to end this and bring her down several notches. Into the ground.
"I don't have time for that," Fluttershy said, the weight of the words requiring a herculean effort to lift from her lungs and past her lips.
Pinkie backed her head up, removing the yellow hoof from her mouth. "Okey dokey lokey," she said with a cheerfulness that had to have been faked after Fluttershy's ruthless rejection. That the pink mare was even standing after that was a miracle in itself. She pronked away, likely in sheer terror, as Fluttershy fixed her with a glare that could melt butter.
Then it was on to the next target of her wrath. She turned around and saw... a mailbox. A mailbox that was soon going to know it was a mistake to be in the path of Fluttershy the Destroyer.
"Hahahaha!" she cackled and pulled back her left forehoof, then kicked it. As she did, there was a sharp pain in her leg, just above her hoof. Probably nothing, she thought, but looked down anyway just to make sure the mailbox hadn't severed the limb from her body. Nope, it was still there. Same as always, except with a thin splinter of wood peeking from her fetlock, and was that blood? Lightheaded and swaying at the realization, Fluttershy fainted, collapsing onto her side in the soft grass.
Fluttershy awoke, feeling an odd mix of well-rested and confused. Grass, wet with dew, pressed against her left side, and she realized that was just how she was lying. A smiling porcelain-white face with a pink mane that matched her own filled her view. She recognized that it was Nurse Redheart.
"Hey, Fluttershy," she said gently. "How ya feeling?"
"Uhh... My head," the pegasus replied, feeling a headache coming on. "What happened? Where am I?"
"Well, it looks like you bumped into this mailbox here and got yourself a little splinter and passed out. Somepony called me and I came over and bandaged it up for you. You were out for maybe five minutes," she explained.
The mailbox.
Fluttershy's eyes widened as memories of the past hour flooded back. The horrific and nightmarish deeds she had done, the shameful cruelty she had subjected Ponyville to. Her face flushed with embarrassment and she felt a strong desire to leave.
"I-I have to go!" she said suddenly, standing up on wobbly legs to flee.
"Okay, well, be careful," Nurse Redheart said, waving goodbye.
Fluttershy thanked her as she galloped away, toward her cottage where she could lament in private. Her run home was panicked, but she made it relatively unnoticed. She ran upstairs to her bed and leapt, face first, into her pillow. Then she sobbed deeply, remembering what she had done. As she cried herself out and finally calmed down, she realized nopony had actually been hurt. Not seriously, anyway. That made her smile.
She realized what had happened. That her stored anger had built up too much, and she exploded. But she was sure it wouldn't happen again.
After all, Fluttershy couldn't explode twice, right?