Celestial sat at his desk, gnawing on a quill and considering the latest paperwork in front of him. The long horn growing from his head and large wings folded at his side identified him as an alicorn, and the cutie mark on his flank, a sun, revealed his role as the master of the sun. His pure white coat was unmarked by even the slightest dirt...
And his mane was pink. Being a demigod with the power over the sun, though, prevented most ponies from ever teasing him about it. The only one who ever did consistently-
There was a knock on the door to his bedroom, and the only pony alive allowed to poke fun at him entered, his sister Luna. She was levitating a black jar filled with blue flowers and had a spark in her eye that tipped off Celestial immediately; she was up to something.
"Hey, Celly!" she cried happily. Celestial winced mentally; his feminine colors had earned him the nickname since the two were little foals, a long time ago by the reckoning of mortal ponies. "I heard you were doing a lot of paperwork, and I know you hate that stuff, so I brought you something to cheer you up!"
Celestial carefully grabbed the vase with his telekenisis, expecting party streamers or paint to explode at him. Luna put on her 'hurt' face and nothing happened.
"Come on! Can't a sister cheer up her brother? I made those for you!"
Celestial felt a little bad, but centuries of having a prank-loving sister taught you caution. He examined the flowers in more detail; they were actually quite beautiful, with wide dark blue leaves and a similarly-colored bulb. The vase was quite pretty, too; it was black with white dots, obviously reminescent of the night sky.
"These are beautiful, Luna," Celestial said honestly, leaning in and taking a deep sniff. They smelled lovely. "Thank you. What are they called?"
Luna's pout face was replaced by a beaming smile. "I don't know, really. All the silly unimaginitive names like Moonrose and stuff are taken. But I'm glad you like them!"
Celestial smiled and got up from his desk to give Luna a hug. "You always manage to cheer me up, Luna," he said affectionately. "With these flowers here I might even be able to force myself through the rest of these papers here."
Luna laughed and nuzzled her brother. "I would love to help, but I have stuff to do," she said honestly. "The whole ruling a country and all. I'll be going over the new tax stuff in my room."
Celestial nodded, understanding the need for work. "Have at it, then. I know you'll enjoy yourself more than me."
"Enjoy yourself, Celly," Luna called out as she turned and left, that light still in her eye.
Celestial sighed but couldn't be angry at his sister after the heartwarming gesture. He sat back down, ready to finish the paperwork with Luna's flowers watching him benevolently.
Luna was reading through one of her tax law books in her bedroom when her door literally exploded into its seperate particles. In her doorway stood Celestial; pink mane flowing as if in a wind, eyes glowing with white energy, great wings spread wide and-
A rounded snout. Luna burst out laughing. Her flowers had changed Celestial into Celestia. She hadn't know what they would do, but she had hoped that it would be memorable, and this certainly was.
Celestia, however, wasn't laughing. "WHAT DID YOU DO?!" she half-asked, half-thundered.
Luna managed to gasp somehting about 'poison joke' and 'random pranks' in-between her laughing fits.
"IS IT PERMANENT? I CANNOT APPEAR TO OUR PEOPLE LIKE THIS!"
"But you're so beautiful! And no, it-" Luna paused. She hadn't thought about the effects of having as much power as an alicorn...
"LUNA!"
Luna looked at the earth from her viewpoint on the moon. It was quite the view. Being banished "indefinitely" was certainly worth seeing Celly turned into Celestia. Too bad her bro- sister didn't realize that not only had Luna planted her flowers in several strategic points in the castle grounds, but in the Everfree Forest as well. Soon, her prank flower would spread to uncontrollable levels. Luna figured that Celly would move the castle to some barren, lifeless desert or mountain after trying and failing to exterminate the flower. Luna giggled again and thought of her next prank; maybe an evil alternate persona bent on taking over the world?
Luna grinned madly as the possibilities opened up before her. These thousand years would go by quickly enough, and she would be ready to come back in full force when she returned.