"I wonder what the Princesses intend to announce," Twilight wondered aloud.

Starlight Glimmer giggled, a dizzy, slightly nervous sound. "Who knows? It could be anything."

Twilight gave a sidelong look at her apprentice. The two of them were standing on a balcony, one of several along the face of the castle, overlooking a broad plaza absolutely packed with ponies. Towering white walls enclosed three sides of the square, leaving it open to the east, towards the rest of the city. A wide balcony, with delicate golden railings, was set into the central, western wall, ready for the Princesses to give their address to their people. Twilight and Starlight's balcony was higher, jutting from the northern wall, much like a private box at the theatre.

Usually Twilight would have expected to be standing - well, if not with the Princesses, then at least behind them, somewhere out of sight from the ground. Not that she thought it was her due, or anything - she'd never really accepted the idea that she was a Princess herself, now - but because she liked to be close to her mentor and friend any chance she got. Still, Celestia's note had been very specific, apologising for summoning her to Canterlot on her birthday, but promising it would be worth her attendance.

Twilight tugged lightly at her blouse's high collar. She'd dressed formally, and in a hurry, in her fanciest white blouse and a long skirt. Stood in the blazing sunshine, she was beginning to regret her sartorial choices.

Somewhat guiltily, she undid the top couple of buttons, and tugged the collar of her blouse a little wider. Beside her, Starlight seemed to be almost alarmingly eager for the announcement to begin, shifting from foot to foot and clutching at the railing with anticipation. Maybe it was the excitement of having been summoned with Twilight; just the two of them, and nopony else.

Starlight drummed her fingers on the railing, then twisted towards Twilight. She opened her mouth, then closed it again, then inhaled, about to speak. Then didn't.

Twilight exhaled, slightly exasperated. "What is it you're not saying, Starlight?"

"You know - sometimes you think other ponies don't know things, and they do. You know, some things that you've written about, maybe, or maybe just didn't totally get rid of, and then they talk to you, and they're like - okay, I can see what you're thinking - and you have no idea they know you're thinking it, and so, one day you find out that other ponies do know things you've kept secret, but it's fine. It's totally fine, and then you get to have the things you want but didn't talk about." The words poured out in a sudden rush, Starlight's cheeks hotly pink, barely coherent.

Twilight blinked, trying to sort through the babble of 'you's and 'they's. Starlight had, what, found out something? Done something?

Uh oh.

A blast of trumpets echoed around the square. Twilight's gaze snapped towards the gilded balcony, where the two Princesses were emerging. Celestia wore a deep red dress, vivid against her white skin, while her sister wore an identical outfit in pure white that contrasted beautifully with her own midnight blue. They were smiling, clasping hands as they waved to the massed ponies filling the square. A massed cheer of welcome rose to greet them.

"Citizens of Equestria!" called out Luna, her voice carrying across the square effortlessly and silencing the crowd. "My sister and I come before thee with an announcement and revelation of great import! Heed our words!"

Celestia stepped forward, squeezing Luna's hand, then releasing it. "Yes, my ponies, the time has come for a change. The time has come for a truth that I have long held back. As of this day, Luna and I shall be stepping down as rulers of Equestria."

Twilight slowly leaned back from the balcony railing, aghast. This was - impossible! Celestia was Equestria, she'd never abandon it! From the babble of voices below, the ponies filling the square were equally in disbelief.

"My ponies, please!" Celestia called commandingly, and the swell of voices slowly subsided again. Then, she smiled brightly. There was something odd about the look on her face - and Luna's, too - something about her eyes, irises too wide, pupils too small. "I'm stepping down so I can truly devote my time to something I love."

Luna stepped behind Celestia, wrapping her arms around the other mare's waist. Then, in a single sharp movement, Luna's dark hands gripped Celestia's bodice and pulled it down, spilling the diarch's breasts into the open air for all to see. Celestia gasped, squirming, beginning to grind her hips back against the pony behind her.

"I'm going to spend all my time fucking my sister!" Celestia panted, into the dead silence.

The crowd exploded into a roar of noise. Celestia didn't seem to notice, or care, her head tilting back as Luna's dark hands captured and squeezed her pale breasts firmly. "Oh, sister, yes! Use my breasts as your playthings!" she groaned, every word carried across the square by the amplification enchantment on the railings.

"Thy heavy breasts are perfect, my sister, nothing could arouse me more! I cannot live a moment longer without the constant pleasure of your tongue within mine sex, your perfect mouth upon mine!" Luna pressed her body into Celestia's, pinning her sister against the railings and biting lovingly at her neck as she squeezed her full breasts together and pinched her nipples.

"Oh, Luna! Luna, yes, show all of our subjects what you've always wanted to do to me!" Celestia moaned, her cheeks coloured a rich pink-red. Shuddering visibly, she turned around in Luna's grasp and stepped to one side, letting the gathered crowd - now shouting - witness the moment she in turn yanked down Luna's bodice. The Princess of the Night's breasts were dark blue, capped with stiff, near-black nipples, and Celestia immediately ducked her head and began to suck on them with desperate urgency.

"Oh! Oh, sister, sister mine, yes! Thou art truly a harlot for my breasts!" gasped Luna, pressing her hand to the back of Celestia's head. "Suck them! Suck upon my nipples the way we have so long wanted!"

Breaking away, grabbing at one of her own breasts and kneading it roughly, Celestia gasped, "Yes! It feels so unbearably good to give in at last! I love the taste of your breasts, Luna! Your perfect tits!"

Taking hold of Luna's dress, Celestia began to unzip it, then immediately exhausted her patience and simply yanked it down.

Luna wasn't naked beneath.

It would have been less shocking had she simply been nude. Instead, a thick black shaft jutted from a slim web of straps, the gleaming black rubber marked with the crescent moon of Luna's cutie mark. Celestia groaned with delight, and dropped to her knees, running her pink tongue up one side of the toy and down the other. "I love it, Luna," she whimpered, eyes glazed. "I love your cock so much. I want to spend day after day, sucking it and riding it."

"N-not - not as much as I adore fucking thy gorgeous pussy, or - or even giving up mine to you!" Luna gasped, slowly rocking her hips back and forth. "Please! Allow me to give myself to you as you so eagerly have to me!"

Kissing her way up Luna's stomach and over her breasts as she rose, all the way up Luna's neck and to her ear, Celestia breathed hotly, "It would be my deepest pleasure, sister." Her magic flared around her as she straightened her back, and her crimson dress simply vanished without trace. There was just enough time to see the golden sunburst marking her own strap-on, before Luna threw herself to her knees and swallowed the shaft into her eager mouth.

"Oh! Oh, oh Luna, you're such a talented cock sucker," Celestia groaned. Seizing a double handful of Luna's flowing mane, she drew back a little, then thrust her hips forward, beginning to fuck her younger sister's mouth with desperate, shuddering urgency. The wet sounds and gasps of the Lunar Princess were broadcast across the entire square, some ponies near-rioting, some trying not to look or listen, others watching utterly entranced by the spectacle. Some were even openly touching themselves. "Swallow my cock, sister!" Celestia hissed urgently.

"Fuck my mouth, fuck my mouth," grunted Luna indistinctly, the words almost too muffled to be made out, desperately playing with her stiff black nipples. One hand slid down to grip her fake cock and began jerking it up and down, grinding the base against her clit beneath.

Twilight watched with wide, staring eyes, clutching the railing with both hands, shocked beyond her capacity to react. It couldn't be happening! It couldn't! Her own body was quivering, so flushed and sensitive that the pressure of the cloth against her tender breasts and bare sex was almost unendurable. She felt an insane urge to strip off herself, and join them, down there on the balcony.

Two things stopped her. One of them was the fact that this was all horribly familiar.

She'd had a dream like this.

She'd written it down.

Then, she'd become hideously self-conscious, and destroyed it.

Or at least, she thought she had.

Which brought her to the second thing.

"Starlight! What did you do?!" she whispered, unable to look away from the two rulers of Equestria, light and dark, openly fucking in the sunlight.

"Ssh! Here it comes!" chided Starlight, overcome with eager excitement.

Luna had broken away from Celestia's toy, though not before she'd demonstrated to the entire kingdom that she knew exactly how to deep-throat a substantial cock, and turned around. Grabbing the railing, bent over with her ass in the air, she reached back to yank her own strap-on free, straps snapping, and cried out, "Fuck my pussy, sister mine! Fill me! Make me thy filthy cocksleeve!"

"It is my - pleasure to grant - your wishes, sister my love!" Celestia panted, mauling her own breast with one hand and pushing it up far enough to lick and bite at her own prominent pink nipple. Planting a hand on Luna's ass, she rubbed the tip of her saliva-slick cock up and down her sister's cunt, then, with a single forceful thrust on her hips, buried the toy within her.

Luna howled in pleasure, loud and uninhibited, her dangling tits swaying as her sister began to roughly fuck her. The slap of skin against skin rang out from the balcony as Celestia's hips slammed into Luna's ass, over and over. Gripping the railing hard enough that it began to bend, Luna declared deliriously, "My sister and I are mere sluts to each other's lusts hereafter! All hail the new Queen of Equestria! All hail Twilight Sparkle!"

Celestia rammed her shaft into Luna's yielding cunt, forcing a keening wail from her sister, and echoed forcefully, "All hail Twilight Sparkle!"

Twilight's jaw dropped. That hadn't been in her dream! Wordless, frozen to the spot as ponies began to turn and look up at her, she finally managed to wrench herself out of her paralysis and twist around.

Starlight had dropped to one knee, beaming brightly. "I perfected my spell, all to give you this!" As Twilight choked, trying to find the words, Starlight looked up at her and declared joyously, "My Queen - happy birthday!"

Author's Note

Yep, I had another story left. I actually extended the challenge to eight days, since I'd had this concept knocking around at the back of my head since day... three? four? ...and I'd avoided doing it so I could pay attention to other ponies, ones I hadn't already used as much as I had Celestia. Still! With the main challenge done, I wanted to lay this one out before I was finished.

Thanks for reading

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