When Sharp Wing woke up the next morning he didn't notice anything was wrong at first. His eyes picked up on the fact that the bed seemed a little bigger than usual, but his brain, which was still waking up, dismissed it. The same thing happened again when he walked past the mirror in the bathroom that was connected to his bedroom. Sharp Wing had a habit of glancing at the mirror every morning as he walked out of his room, so it was entirely natural he didn't expect to see anything different. Technically his eyes registered that his body had changed dramatically, but not his mind. Sharp Wing poured himself a bowl of frosted oats with little sugar cubes and marshmallows in it, took a shower, brushed his teeth, made a weak attempt to comb his mane, and walked out the door.
This time both his eyes and mind noticed something, a streak of cyan blue that seemed to be getting bigger. Then it hit him. The pain Sharp Wing had experienced when he hit the tree branch yesterday was nothing compared to the bone-crushing force he felt now as he was shoved back into his house and slammed up against the blue drywall of his bedroom. This time when Sharp Wing opened his eyes his vision was filled with the colors of the rainbow.
"Why hello, Rainbow Dash. What a surprise," Sharp Wing groaned.
Rainbow Dash grunted and peeled herself off of him.
"Ow, Sorry about that, Sharp Wing. Word of advice, don't try to do a barrel roll at high speeds. It hurts," apologized Rainbow Dash, completely unaware that Sharp Wing already had a very good idea of how much it hurt.
Rainbow Dash shook her head and looked at the pegasus she had practically flattened. Then her eyes widened and she shook her head again, blinking to make sure she wasn't seeing things.
"I must have hit my head really hard," she muttered.
"Well, that's better than hitting something you actually use from time to time," Sharp Wing snapped.
"Um, Sharp Wing, are you aware that you're now a mare?"
"Oh, that's such a mature and clever insult. I haven't heard that one since I was in flight camp."
In response Rainbow Dash grabbed his shoulders and dragged him to the bathroom.
"Ow, what are you- are you trying to give me a swirlie?"
"Shut up and look in the mirror."
Sharp Wing did so. The first thing he noticed was the usual. Blue eyes, light gray coat, long feathery brown mane. Then he noticed his eyelashes.
"What the-" he breathed, moving closer to get a better look.
Not only were his eyelashes more pronounced, the shape of his head had changed too. Sharp Wing's jaw had never been very large to begin with, but now it was noticeable smaller. Sharp Wing stepped back to view the rest of his profile. His entire body was different. Instead of his thick leg muscles and generally stocky build he had become more streamlined and shorter. Sharp Wing stepped back to be besides Rainbow Dash and compared his height to hers. Instead of being taller than her they were now equal in height.
"No, this- this- it can't-" she stuttered in disbelief.
"But it is," observed Rainbow Dash.
Abruptly Sharp Wing spun around and pinned Rainbow Dash against the wall.
"What did you do?!" Sharp Wing screamed in a high-pitched voice.
"Let go of me!" Rainbow Dash yelled as she tried to vain to break free.
"You changed me into a mare!"
"No I didn't! You did that yourself!"
"You slammed into me and I turned into a mare!"
"That doesn't make any sense! You can't knock ponies into another gender!"
Sharp Wing relaxed her hold. She was right. That didn't make any sense.
The split second Sharp Wing's hold relaxed, Rainbow Dash slipped loose and reversed their positions. Sharp Wing was now the one pinned against the wall.
"Nopony pins me against a wall," Rainbow Dash hissed.
"What are you going to do about it? I'm bigger then you," Sharp Wang snarled, forgetting for a moment that she wasn't.
Rainbow Dash's magenta eyes glowed with fury.
"Not anymore you're not."
Sharp Wing braced her fore hooves against Rainbow Dash's and the battle was on. Doubtlessly there had never been a battle like this in Equestria before. Two mares, both of whom possessed what many would call masculine personalities, in the bathroom, engaged in a contest of physical prowess. The two of them gave it their all, neither budging, locked in combat. After several minutes in this stand-off their tempers waned.
"Truce?" offered Sharp Wing.
"Truce," agreed Rainbow Dash.
Both of them went down on all four hooves again.
"Let's go to my living room so we can figure this out," suggested Sharp Wing.
Sharp Wing walked out of the bathroom and sat down on her armchair in her living room as Rainbow Dash flopped onto the couch.
"I know for a fact you were a stallion yesterday, I saw you at the party," Rainbow Dash noted.
"Sompony would have noticed if I had started to change at the party," Sharp Wing figured.
"So it must have happened afterwards. When you were alone."
"But all I did was fly straight home and go to sleep."
"Maybe Twilight can help figure this out," Rainbow Dash suggested.
"Or Night Mist, he is a detective after all," mused Sharp Wing.
Then she changed her mind.
"Actually, I'll go with Twilight."
"Why Twilight?"
"I know for a fact that Night Mist would laugh at me. I'm willing to bet Twilight Sparkle will be a lot more sympathetic."
Sharp Wing and Rainbow Dash took off from the front door of Sharp Wing's home and flew to the library. Sharp Wing's sword sheaths kept slipping as she flew. The straps were a bit large on her now. But she didn't bother to try and fix it. Surely Twilight Sparkle would have a spell to change her back to her normal form and then it would fit again. The two peagasi landed on the balcony attached to the tree that was home to Twilight Sparkle and the library.
"Is there a reason we're not using the front door?" asked Sharp Wing.
“Front doors are for chumps," Rainbow Dash explained as she rapped on the glass.
Twilight Sparkle, who had been reading a book, nearly jumped out of her skin when she heard Rainbow Dash knock.
"You know I hate it when you do that," said Twilight Sparkle as she glared at Rainbow Dash through the window.
"That's why I do it," Rainbow Dash smirked.
Twilight Sparkle sighed as she opened the balcony door.
"Who’s your friend? Somepony you know from flight camp?" she asked.
"Wait for it." Rainbow Dash told Sharp Wing.
Sharp Wing sighed as Twilight Sparkle studied her.
"Are you-" Twilight Sparkle gasped with wide eyes, unable to finish her question.
"Yep."
Twilight Sparkle burst out laughing.
"Thanks for your sympathy," Sharp Wing growled.
"Oh my gosh this is so rich! I- I- oh my gosh I can hardly breath- Spike! Come here! You need to see this!" exclaimed Twilight.
Spike rushed into the room.
"What is it?" he asked.
All Twilight Sparkle could do as she laughed was point at Sharp Wing.
Spike scowled at Sharp Wing.
"I don't get it. Who is- wait."
His eyes widened in disbelief.
"Are you-"
"Yep."
Spike roared with laughter.
"Oh my gosh that's hilarious! Where's Owlilicious he needs to see this! Owlilicious!"
"Who?" an owl called out from another room.
"It's Sharp Wing! He's been turned a mare! Come see!"
"Who?" Owlilicious called again.
"Sharp Wing! He’s a- oh never mind."
By now Twilight Sparkle had regained some control.
"I'm sorry, I shouldn't laugh. I suppose you're here because you want me to change you back to normal with magic."
"That would be nice."
"How did you change in the first place?" asked Spike.
"No idea."
"Spike, fetch me the glossary of every spell known to ponykind."
Spike dashed off and returned with the book Twilight Sparkle had requested.
"If there's a spell for changing sex it’s probably under "s"," muttered Twilight as she flipped through the pages. "Nope, nothing for changing sex."
"What about "g" for gender?" suggested Spike.
Twilight Sparkle flipped to the "g" section.
"Aha! Here it is!" Twilight Sparkle exclaimed.
Sharp Wing breathed a sigh of relief. Soon she would be back to normal.
"Oh wow, what are the odds?" Twilight said as she read the page.
"The odds of what?" asked Sharp Wing carefully.
"Did you know that there are over six thousand spells known to ponies?" She asked Sharp Wing.
"Um, no."
"And only one hundred and ninety three have ever been proclaimed as taboo?"
Sharp Wing didn't like where this was going.
"Please don't tell me the gender changing spell is forbidden."
"Actually, it’s called the gender bender spell and yes, it’s forbidden."
"Gender bender. Catchy," remarked Rainbow Dash.
"But why is it forbidden? Can you do it anyway?" asked Sharp Wing, crushed.
"I have a book of reasons the one hundred and ninety three are forbidden. Spike, could you-"
Twilight Sparkle was interrupted by Owlilicious dropping the book in front of her.
"Never mind, Spike," she said as she flipped through it.
Once she found it she started reading it out loud.
"The Gender bender spell was outlawed by Emperor Steel Horn Featherblade when-"
Twilight paused and looked at Sharp Wing.
"Isn't your last name Featherblade?" she questioned.
"Yeah, I'm a direct descendant of the Featherblades who ruled Equestria," Sharp Wing sighed.
"Seriously? That's so cool!" said Twilight.
"Can we get back to finding out why the gender bender is forbidden?"
"Wait, hold up. If you're a direct descendant of the Featherblades that means you would be the ruler of Equestria if Princess Celestia and Princess Luna hadn't been born," Rainbow Dash deduced.
She hadn't been the first pony to make that assumption. It was an assumption Sharp Wing had been trying to correct in others her entire life.
"Actually, most historians agree that if Princess Luna and Princess Celestia hadn't intervened Equestria would have wiped itself out in civil war. I wouldn't be the ruler of Equestria because there would be no Equestria to rule. Even if it didn't die out there are still plenty of other Featherblades who still carry the last name. Now can we get back to the task at hoof?"
Twilight shrugged and resumed reading.
"The Gender bender spell was outlawed by Emperor Steel Horn Featherblade because anypony who was changed by it would be mentally scarred for life. Worse yet, If a pony had been changed and was unable to get changed back within a week they would, without exception, go completely insane."
"Well that's just wonderful. I feel so much better about the whole thing now," Sharp Wing said sarcastically.
"Would anyone alive today know the gender bender spell?" asked Spike.
"No, when a spell is forbidden it’s against the law to teach it to others on penalty of death," said Twilight.
"Well that seems harsh," remarked Spike.
"Not as harsh as the effects of a taboo spell."
"Maybe Princess Celestia or Princess Luna would know it?" suggested Rainbow Dash.
Sharp Wing knew the answer to that one.
"No, Princess Celestia and Princess Luna were born during the reign of Emperor Sharp Wing, three generations after Steel Horn."
To this day Sharp Wing had never understood why her parents had named her after the psychotic emperor who had tried to kill Princess Celestia and Princess Luna.
"So we're stuck." said Spike.
Sharp Wing mentally cursed her ancestor for screwing her over.
"Maybe you should pay a visit to the hospital," recommended Twilight.
"I think I will. Magic has failed me, but surely science will have an answer!" proclaimed Sharp Wing with renewed hope and vigor.
Without hesitation Sharp Wing took off from the balcony and flew away.
Twilight Sparkle, Rainbow Dash, and Spike watched him go.
"He's doomed, isn't he?" said Spike.
"I'd be surprised if he didn't go insane by the end of the day," remarked Rainbow Dash.