It was a spectacular sunset, Celestia's sun quickly swallowed by the sheer awe of her younger sister's luminescent night sky, the blues against the myriad of other colors. Walking down from the tower, Princess Celestia passed Princess Luna, their respective plots just barely squeezing by on the narrow staircase. Celestia looked back as her fur brushed past her sibling's.

"Enjoying the view of thy magnificent rump, Madame Sunbutt?" Luna bragged about her own magnificent moons, even going as far as to press her rear against her elder counterpart's as to measure the width of each cheek in comparison.

"At least I haven't been eating snacks while doing nothing but sitting on my fat plot, Queen Sedentary." Truth hit Luna like a hard mallet: her free time consisted of reading books and eating whatever was brought within the same room as her. Celestia harrumphed and headed down to her chambers to get a half-decent night of sleep.

Sufficing for a giggling fit, Luna walked upstairs and onto the tower to take the moon on the first part of its journey across the night sky. As her horn glowed, her mind felt a slight disturbance, a sliver of unintended magical force running through the hallways, the dark violet mist swirling unseen into Luna's chambers. Barely taking note of anything odd, she walked down the staircase, into her chambers, and immediately collapsed in shock.

Nightmare Moon was laying on Luna's bed, ass towards the door, with history's most sultry, drop-dead look on her face. Her dark helmet and armor twinkled in the moonlight, her flowing mane of ethereal mist and miniature stars castling a slight shadow across her face.

"I was hoping tonight was going to be a full, blue moon." Her voice was silky smooth, with no hint of malice; just loving and lust for her dear fat counterpart.

——————•

Luna stirred ungraciously some time later, her memory stretched thin and hung out to dry. How she got there was hazy; she remembered walking in, something surprising her to the point where she fainted dead away. Realization kicked in that she couldn't breathe, couldn't see, couldn't feel. An amorphous blob of fur and fat pressed on her face, jet black both from a visible standpoint and where she lay under Nightmare Moon's fat ass.

"It's nice to see you again, my Princess." As Nightmare Moon lifted herself and her enormous plot off of her, she couldn't help but be mesmerized by her evil counterpart's plot. Luna unceremoniously started mumbling to herself, keeping a conversation with her mind, trying to grasp how an alicorn, never mind a pony, could have that kind of ass. Easily two, maybe two and a half feet wide; midnight black, blue splotches on either side giving away her cutie mark's location; a set of lips that would put any pony that dared to compare in shame without even looking; a puffy pucker, hyper-sensitive to even the smallest of touches.

Luna could do nothing but stand there, slack-jawed, as the nightmare began. Luna was shoved to the ground with a bump of the rump, and the dark alicorn prepared her tongue while lowering her plot on her Princess of the Night.

"I will make this offer once: A lick for a lick, a moan for a moan, a climax for a climax. Anything you have ever cared to attempt that involves my ass or yours. Tonight only. If you do we'll enough then I shall leave, only to come back if you should ever want more. Either that, or I take over Equestria once again. Your choice, except, oh; you really don't have one. Good luck, my Princess."

"And good luck to you, Moony." Bowing their heads, they set off on a journey; not of hardships, but of pleasure.

—————•

"Let's start off with some simple facesitting, both going at once. A zero, if you will." A zero is the Equestrian version of a 69. Soon, Luna and Moony were deep in each other's plots, nipping, licking, sucking off the other's clit. Soon, they both felt the familiar pressure of climax build up, and with screams of grateful pleasure for a previous soundproofing spell, came onto each other's faces. A silent few minutes passed, and Luna sneakily performed a spell used more for pranks than anything; of course, turning ponies' digestive tracts against them while processing food was a very evil prank, but she, for once, performed it on herself, adding a few bits of carrion and rotten eggs into the mix. She became a lot thinner as her fat was transformed into an intoxicating, vile gas.

She sought revenge against her well-endowed captor, and her her plot rip unceremoniously throughout her chambers, directly into thwarting open mouth and nose of Nightmare Moon, forcing her effluence down into the throat, taking her time as the Princess of Eternal Darkness stirred, and soon lay on the floor retching and threatening to vomit. Anti-magical chains were wrapped around her hooves, and likewise with a ball gag and magic supressor. The dark alicorn could do nothing but whimper pitifully as Luna cackled at her shadowy self. "I have waited so very long for this moment of destroying you with my own plot!" The last of her fresh air for weeks was taken as the cacophony of sputtering noises came out from the Ruler of the Night, the captive blinding the prey.

—————•

Nightmare Moon, the infamous alter ego of Princess Luna, was trapped under a blubber volcano, which was spewing out gas by now. The endless torrent of flatulence, luckily, gave her a source of air, however dank and nasty it may be. She had been down under for about 5 minutes when she realized that her gas was edible, and a cunning counter-attack that would put the most skilled guardspony to shame. She forced herself to push out her ball gag enough to ingest several toxic clouds that were slowly getting worse, but not enough to make it obvious that said gag had been removed. Once the allotted amount of gas had been secured in the stomach, she forced herself to lick Luna's pristine pucker.

The plan worked perfectly as the Princess of the Night writhed in pleasure, tons of gas traveling down Nightmare's esophagus and windpipe, until every breath outward smelled even worse than when it went in.

"What goes around comes around, my dear Princess." Nightmare Moon launched a nasally assaulting burp as she went in for the kill; the smell of Luna's gas attacks mingled with stomach acid simply demolished Luna's anal assault. She let out the longest, most malodorous fart in the history of ponykind. Nightmare Moon, fueled by corruption, had corruption turned against her, and became a slave to Luna and her farts. As the fart reached its climax, Moony shoved her tongue inside the jet black anus to get the full taste, feel, and smell of flatulence rolling across her tongue, accomplishing nothing but making the fart more powerful.

She had a lasting thought; now would be a very, very easy time to try anal. Pulling into her magic reserves, she summoned an extremely realistic, anatomically correct horse cock on both her and Luna. Eternal Night pounded the twin moons of Luna's flank, each thrust causing small squeaks of pleasure, jiggles of both royal plots, and a very obnoxious ripping sound from the Alicorn of the Night. Hilt to tip and back to the hilt again. The familiar throbbing came again, and they came at the same time from both ends. Luna's rosebud clamped like a vice while both of their dicks came in unison with their more familiar set of genitals amplified the climax hundred-fold. Both royal alicorns barely managed to stay awake, and decided that, since they were too busy breathing to speak, telepathy was a good idea.

Luna, I challenge you to a staring contest. Her voice was husky, and by the time Luna was able to look up at her new friend, Moony was motioning towards her extremely pliable rump.

It. Is. On. Luna decided that standards should be set. No touching of the genital region, however, hooves may be used to break concentration while massaging or spanking the flank. She smiled at Moony, as if she knew she was gonna win.

A strange tingling was felt on her underbelly, and the futa-cocks disappeared. I highly doubt those will help either. No reward for winning, and no reward for losing. This is just for fun, okay, Princess?

Understood, my sweet Nightmare. And with that, the staring contest began. Transmission of telepathy was severed between the two split personalities as each perfect rump was stared at for hours on end: Plot hairs were counted time and time again, wrinkles on their rosebuds studied with deep thought that would impress the philosoponys of the day, tail colors analyzed, compared, and contrasted with detail that would put Twilight Sparkle to shame. Eventually, as all ponies must do, they fell asleep at the same time, right as the moon was supposed to set.

—————•

"Luna! Did you fall asleep again?" Celestia muttered to herself about how her lazy sister couldn't even stick to the same schedule, even snacking in her sleep on one occasion. After disarming all the spells, she came upon the soundproofing spell, which would simply not budge. Luckily, it was fading away fast, and when it finally vanished, she swung the massive doors open, and almost fainted dead away in horror.

In front of her, the scene of the crime spoke for itself; gallons of various mixed fluids, fetid air thick enough you could cut it with a knife, and her beloved sister using her evil counterpart's head as a seemingly amazing pillow, with Nightmare Moon doing the same. Both of them reeked of sex and flatulence, and Luna had a thin line of drool crawling down her Nightmare's flank, occasionally dripping onto her nether lips, the dark alicorn's not as pronounced, but still there. Both parties had on the cheesy smiles of afterglow plastered on their faces, even in their sleep. Eventually, Luna awakened, and was met with the unusually stern look of one Princess Celestia.

"You have a lot of explaining to do, young miss."

Author's Note

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