It began as a day like any other. Princess Luna sat fidgeting on her stool, darting her eyes about the room. As was her usual method of "paying attention" in one of Starswirl's many lessons in magic. Her mentor was busy doodling some odd equation on the board. Honestly he couldn't tell you where he found the patience to deal with her but he did. One thing was clear though, she definitely had shortened his lifespan with all her tom-foolery.
He placed down the chalk piece he had been writing with. "Luna, my dear, you're doing it again."
She stopped her silly movement immediately. "D-Doing what exactly?" She flashed him her most brilliant, innocent looking eyes.
He placed a hoof to his forehead, sighing deeply. "You're not paying attention to the lesson, again. That is what you are doing, Princess."
"But," she protested. "it isn't my fault! This stool is sooo uncomfortable that it nearly drives me mad! And why am I the only one that has to sit through these boooriiing lectures anyway?"
She could tell she had maybe upset him by the way he used his magic to pick up the chalk and flick it at her. It hit with enough force to leave a tiny white streak across her forehead. Thankfully she didn't mind too much.
"Honestly Luna, you know full well that if it wasn't for your 'mishap' yesterday you'd have a proper chair to sit in. And Celestia, on the other hoof gets the day off for actually practicing and committing the knowledge contained in my lessons to her memory. Any student should strive to do the same!"
"That's not fair! And did you forget I am royalty? I need a suitable furnishing to rest my hind quarters on. So why can't we just go and get another chair?"
Starswirl pulled out a list of all the citizens in the entirety of Equestria. "You see this, Luna?"
She winced. "Y-Yes, what of it?"
"You've gone through a lot of chairs." He bowed his head, almost as if in shame. "More than there are pony's in this land. They've had a hard time recovering from the loss as of late. Because of you, little Billy doesn't have a chair to sit on. Do you know where he sits now?"
She opened her mouth.
But he didn't wait for her answer. "The ground is where he has to sit. At least until the nice carpenter pony's finish making him a new chair to sit upon. So let this be a lesson for you to be more focused, studious and cautious in the future when using magic. Why, a proper spell could turn that old stool into a pretty decent chair if you would only put your mind to it..."
Luna placed her hoof to her face and her eyes now began to water. Had he gone to far this time? It certainly wasn't his intention to make his pupil cry. He placed a comforting hoof on her back. "There, there, my dear. Little Billy will get a new chair in no time at all! I know you didn't mean to engulf in flames, disintegrate and shred all those poor defenseless chairs."
"No, it's not that..." She plugged her nose with both her hooves now. "It's the...the s-smell."
"What sm-" Just as he pondered what in the blue blazes she was talking about the pungent odor drop-kicked him in the nostrils. "My word! It smells like it would if Chancellor Puddinghead's hat were filled with some vile chocolate pudding looking substance that wasn't chocolate pudding at all. And then it were left to putrefy for a fortnight in a room filled with cut open, aging Limburger cheese."
Luna blankly stared at him, eyes still watering and nose still plugged up tight. "Your description of that makes my head hurt. But it is accurate."
He breathed in the odor again, seemingly unfazed by the toxicity of it all. "But where in Equestria could it be coming from I wonder?"
"Well it smells like somepony farted to me." his pony Princess companion said plainly.
Starswirl gasped in shock, becoming beet red. "W-Why I never! Of all the accusations!"
By now she had caught on to his meaning. A tinge of scarlet decorated her cheeks as well. "I-I wasn't blaming you. You're the one accusing pony's of things."
"But there isn't anypony else here to blame the flatulence on. It's just the two of us, all alone in here."
She grew increasingly annoyed with the whole situation and often that led her to say things probably best not said. "Well maybe it was you. You're awfully defensive about all of this. But don't worry about it. You can't help it after all, given your age. At least that explains the potency of the smell."
Starswirl narrowed his brow, getting closer to Luna's face. "Young lady, how dare thee! Maybe it was you who has offended. Yes I see it now. It was all that fidgeting around on that flat faced stool of your's, it must of rammed air up into your derrière! Only natural my child that it should come out as foul smelling as you are rotten on the inside!"
Luna retaliated, rearing up and going into her full royal voice. "WE ARE NOT ROTTEN! IT IS THEE WHO IS ROTTED INSIDE! AS YOU ARE SO VERY OOOOLLLLLLDD!"
Starswhirl smirked. He took off his hat and roughly shoved it over Luna's nose and eyes as he patted it down. "The same insult about my age again? Tsk, tsk, it would seem the dim light of the moon fits you perfectly compared to Celestia's shining brilliance!"
Luna flung off his hat and stuffed it back down on his noggin, making extra sure it was nice and snug."PERHAPS YE WOULD LOVE A CLOSER LOOK AT THAT 'SHINING BRILLIANCE' YOU ADORE SO MUCH AS I HURDLE YOU INTO THE SUN! THAT IS IF YOU CAN EVEN SURVIVE THE JOURNEY BEFORE WITHERING AWAY, OLD STALLION!"
"The MOON!" Starswhirl pointed to her flank. "Your backside is the very SYMBOL of one's hindquarters!"
2 Minutes later...
Celestia smiled, humming a happy little tune to herself as she trotted down the hall to check in on her Sister's magical journey. She hoped it would be better than all the previous ones and that Luna had finally become serious about learning proper magic.
She opened the door to the classroom.
Starswirl was on one side of the room, bent over with a sloppily painted red X across his posterior as it was pointed out toward Luna who was on the other side. Her horn was aglow, eyes narrowed and her tongue hanging out the side of her mouth. Celestia recognized that immediately as her Sister's concentration pose.
"Now I hope you remember," Starswirl said. "how to cast it, yes? Just aim for the red X and you can't go wrong."
Celestia cleared her throat, breaking into their little world. "Starswirl, Luna, what is going on here?"
"Umm, uh, a-" The usually genius Starswirl was a bit dumbfounded. "I-It is a spell to determine..." he coughed suddenly. "To determine if I f-farted."
Luna just smiled, turning red again.
Celestia winced and nodded slowly. "Okaaay, I guess whatever you can do to get Luna interested in magic." She blushed and looked away before taking a snap glance back at the scene. "I'll just leave you two to it then!"
Starswirl started to walk to his best pupil. "I feel I should exp- ohaoahoo!" Without warning he felt his butt being zapped with the aforementioned spell.
He looked at the afflicted area. "Ah, excellent Luna! As you can now see, by my bum's blue glow I am indeed not the offender! For if I were it would glow bright yellow!"
"I've never heard of such a spell." said Celestia. "Can I try it out on Luna next?" she smiled with joy at the prospect.
"Hold on there, my sister. I have already been proven innocent!"
"Hmm..." Starswirl eyed Celestia. "Indeed. If Luna did not fart and I did not toot. Then perhaps it was you Cele?!"
Celestia backed up until she hit the wall. "N-Now hold on, how could I? I was in another room far and away from you two. There's no way-"
Both Luna and Starswirl zapped Celestia's rear.
"Well, would you look at that!" Starswirl beheld the results. "It glows bright yellow!"
Luna fell over with laughter. "Celestia, you pooted!"
Three seconds later
Celestia walked over to her sister Luna who was struggling to contain her giggling as she hovered over the fast asleep Starswirl.
"Enjoying yourself?"
Luna flinched, nearly loosing control over the dream she had been manipulating. "C-Celestia, uh, how long have you been standing there?" She looked up at the dream cloud over her teacher that acted as a view port into his dreamworld to make doubly sure of it's stability.
"Oh, long enough." Cele smiled. "So, 'Pooted' Luna, really? Must you trouble him with such bizarre dreams?"
Luna gently closed her connection, letting the dream drift back into his control. "Well he makes me study and challenges me and-"
The Sun Princess simply gave her sister a piece of paper.
"What is this?" Luna questioned, reading it's contents.
Celestia playfully tilted her head back and forth. "Oh, I don't know. Maybe it is his favorite pancake recipe and you can make it for him tomorrow morning as an apology."
"But if I apologize with pancakes he'll want to know what I'm apologizing for. Do you think these things through Cele?"
Celestia only shook her head.