A Lethal Puzzle

Rarity peeked through her curtains at Carousel Boutique. She held Sweetie Belle close as the locked the door and barred the windows.

"Rarity?"

"Yes, Sweetie Belle?"

"Why are you locking up?"

"Well," the older unicorn explained, "do you remember Miss Cheerilee explaining what to do when a madpony comes to Ponyville?"

"Yeah, why?"

"A madmare has escaped from the Ponyville Asylum. The sad part is... I know her."

"Really?" Sweetie Belle asked, her voice a whisper.

"Yes, really," Rarity whispered, "her name is Puzzling Insanity. She was always... umm... different."

"Like Derpy Hooves?"

"Y-you could say that, yes," the big sister continued, "she was... socially challenged. She always preferred to play alone. Now, everypony else besides Derpy and Fluttershy made fun of her because she was different. She'd always run to me for comfort and guidance. And then one day... she snapped. She walked right up to a filly who was especially cruel to her, and... right in front of everypony... bucked her into a wall and stabbed her with her horn. Puzzling tried to get the bully off of her, but her horn ended up breaking off in the other filly's chest. Miss Cheerilee called the police, and the poor little filly was arrested and sent away to the Ponyville Asylum. But somehow... she's escaped. How anypony can use magic with a broken horn is beyond me, but those doors can only be unlocked from the outside... unless magic is used. She was the last unicorn to be sent to the Asylum because of this."

"So, your friend escaped?"

"I was the only friend she had," Rarity sighed, brushing a tear from her eye, "and I can't help but feel somewhat responsible for her imprisonment. I could have stopped them from pushing her over the edge."

"We have a filly like that at school," Sweetie Belle informed Rarity, "and she seems just fine. Miss Cheerilee spent a whole day explaining why the filly is the way she is. She called it 'autism'."

"I never thought of it like that," the royal-maned pony said, "I always thought she was just shy. We didn't have a term for it back then. Not many ponies had it."

"But was the madmare your friend, too?"

"Yes. I feel bad for not standing up to them."

"At least you tried to make her happy."

"Yes... I guess I did."