Author's Note
This work is based heavily on trash anons piece of artwork, I might add more chapters with other characters paired with the Princess, depends how this one goes.
Alone in her stall
Celestia swore this would be the last time took her sisters advice.
"Use the middle stall at Lucky's pub, she said. It will be fun, she said..."
Celestia should have known that Luna's plan wouldn't work, but she was so frustrated at the time that she would have tried anything. You see, life was difficult for a mare like Celestia for many reasons. The pressure of the public eye, the mediation of trade deals with foreign lands, but most of all, the monstrous white member that put even the largest of stallions to shame. This fact, in addition to her high public profile meant finding a mate was nearly impossible, the tabloids would be in a frenzy.
This brings us to Celestias current situation, stuck in the middle stall, cock hilted to the rough wodden surface, the not large enough hole acting as a cock ring, keeping her at full erection. Celestia dare not try to telport for fear of losing such a sensitive body part and she dare not call for help to alert ore ponies to her unfortunate situation.
The worst part of the whole ordeal was that even if the glory hole did work as intended, Celestia's stature would prevent the Anonymity of the act, her fore hooves draped over the neighbouring stall and her head adorned in princessly regalia showing over the top.
Celestia's ears perked up and eyes widened as she heard the bathroom door open and a set of hooves clack against the tiled floor. The steps grew nearer until they stopped in front of the stall occupied by her
"Hmm occupied" said the unknown pony
Celestia let out a breath she didn't know she was holding, her relaxation was short however as the turn of the lock came from the neighbouring stall... and a very familiar pony walked through.
"FLUTTERSHY?!" Celestia realised her mistake and covered her muzzle with her hooves.
The offending pony looked up in shock at her discovery and tried to scramble from the stall, only to be met with the door slammed in her face by a golden glow of magic.
"P-p-p-princess?" came the reply from the stunned mare.
"Yes Fluttershy, it's me." " I need you to help me out of here, Luna sent me here to let off my frustrations but as you see I'm stuuuu--"
Celestia's speech tapered off into a stupid groan as a pair of yellow hooves grabbed hungrily at her shaft. The princess looked down in stunned silence at her partner, just in time too, as she got to see and feel the mouth of the element of kindness stretch itself around her girthy maremeat.
A set of muffled groans met the bathroom air as the yellow pegasus mercilessly shoved as far down the spire as she could manage, coming just short of the thick and throbbing medial ring. The princess took a metal recording of the sounds of the much smaller pony choking and swallowing over the pre drooling python lodged in her throat.
Just as fast as it began, it ended. Fluttershy pulled back to get some air.
"That should be good enough" spoke the short of breath Pegasus.
The princess just looked on, still stunned to silence, as the element of kindness turned around, hiked up her tail, and mashed her lower lips against the slightly flared head of her penis. A moment of resistance, then furnace like warmth as the sun princess got half of her immense rod devoured by the stretched lips of one of her students friends.
Celestia could only watch as the cock hungry mare slammed her body up and down her marecock, gaining ground with each thrust until Fluttershy's distended lower lips swallowed the extra thick medial ring and then clenched down HARD.
The moans from the yellow pony sounded almost painful, mare juice managing to squirt past her stretched entrance to cover the still untouched parts of Celestia's mare breaking cock. Fluttershy may have found her release but the princess was stall as hard and throbbing as ever, perhaps even more so at witnessing such a powerful climax.
"Fluttershy, please, more" Celestia begged through the sound of ragged breathing.
Fluttershy looked back up at the flustered face of her princess and nodded. She slowly removed the still hard cock by walkinf forward, swaying her hips as she did so. The princess expected for the pony to finish her off with her hooves and mouth but she certainly wasn't complainign when she felt the worth of the pegasus' rear.
It was arduous work but with each shock like burst of pain delivered to the Pegasus' rump, and equally powerful blast of pleasure was given to the sun monarch. That was until the flared head finally found its home, nested into Fluttershy's ass. A howl of pain and a jet of pre cum offset each other.
"P-princess, I'm too tired, use your magic"
It was almost like a switch was turned in the Princesses mind, a young tight mare was asking her to take control and give her a good rutting, how could she say no? A golden aura surrounded the yellow pony as she was gently, yet forcefully made to sit down the large mare cock.
Listening carefully for sounds of pain or discomfort, Celestia continued to stuff her seemingly endless tool inside her mates butthole. That was until she broke the plane of one ring with another and felt a warm slash of more juices rain upon her hind hooves. Taking this a sign to continue The princess force the mare down further. The princess could feel it in her loins, it wouldn't take much more to set her off. The Princess decided to end it, using her magic to turn Fluttershy belly up she slowly withdrew the smaller pony off her rod. only to slam her back down to the stall wall, totally concealing the twenty plus inches of maremeat within her. That wasn't the most amazing thing about their coupling, the larger than life bulge that ran from Fluttershy's groin to torso is what really turned Celestia feral.
With little regard of the smaller pony's feeling, Celestia brought Fluttershy up her rod once more and then viciously slammed her back down, shaking the wall between the two stalls, then she did it again, and again, and again. She turned the Element of kindness into a portable yellow sex toy as she ruthlessly pummelled her with her cock. To Fluttershy's credit she was enjoying the rough treatment, moaning wantonly throughout the whole ordeal.
The next thrust was Celestia's last, and with a hint of irony she wished to continue, but alas with the final thrust came her climax, she kept Fluttershy pinned to her base through the whole two dozen or so jets of thick cream delivered straight to her intestines. The aftermath was glorious, floor covered in semen, a pregnant looking Pegasus mare, and a Princess penis now flaccid enough to recede through the hole in the wall.
Maybe Luna's ideas aren't so bad.