Trapped in stygian darkness, the unicorn known as Rarity fought for her very soul itself. She had been visiting the home of a friend, when a fiend who wore the face and body of her beloved princess had materialized from the aether itself, to wreak havoc in the form of black shapes that moved and flowed like nothing living could or should.

Her and her friend Applejack had tried to fight back, only to find themselves snared and enveloped in flowing darkness that bound both of them in place, closing off her magic even as it flowed up over her head to close off the light.

Then, as if from some horrible story, the thing that was binding her in living chains began to whisper into her ear, telling her that she was no longer Rarity. That her destiny was to become a pony known as “619” and that her purpose would be to serve as the helpless erotic plaything of the mare that dared to call herself, “Celestia”.

It was a purpose that Rarity denied and made as clear as she could to the ebony demon holding her, and despite the fact that her mouth and tongue were as bound in place as the rest of her body was, the thing understood her, and whispered a phrase that chilled her to the bone.

“Beginning standard conversion procedures for 619. You will obey Control. You will learn that obedience is pleasure, and pleasure is obedience.”

From that moment on the suit of symbiotic living latex had been having its way with her. Both of her most intimate openings were enveloped, penetrated and thoroughly despoiled in ways that even Rarity’s most salacious novels had only ever hinted at. When combined with the most erotic and expertly targeted stroking and teasing Rarity had ever experienced, she found herself being unwillingly brought toward what promised to be an earth shattering orgasm.

But then, just as she was about to peak, the fiend asked her, “Will you obey Control?”

Lightning blazed in her core as she denied the demon, refusing to let her mind and will be shaped like clay. The powerful shock it delivered straight into her intimate parts utterly destroyed the impending paroxysm of pleasure, leaving an aching emptiness behind in its wake and for the next few breaths Rarity waited for the torture that was sure to be her punishment for refusal.

Only to feel the sheath about her body start its ministrations again. Once more shafts slid along her sexual passageways, twisting and even vibrating. Once more, her nipples were pinched and stretched, her delicate button lavished with attention, causing it to stiffen as a salute to the orgasm that once again was being built inside of her.

And again, just as she was about to climax, as she was about to experience the craved for release of the building erotic tension, came the question:

“Will you obey Control?”

In the few moments of breath she had after the second searing shock, Rarity realized how her captor meant to break her, and as the cycle of erotic torture began yet the unicorn threw herself against her bonds in a desperate attempt to escape, only to find as Twilight had before her, that the suit’s restraints were more than adequate to hold a pony as motionless as it chose to.

The third denial and shock came and went, and Rarity would have wailed in despair if she could have. Escape was impossible. Her eyes could see nothing but the infinite blackness of the living latex hood that covered her eyes. Her ears were fully stopped up, allowing only the sound of her breathing and the voice of Control, telling her to obey, that obedience was pleasure and pleasure was obedience.

As the cycle repeated yet again, Rarity could feel herself starting to unravel. With nothing external to hold onto, and only the endless cycle of building sexual pressure within her: the mantra of Control started to echo in her mind, filling it, becoming her thoughts. She could feel herself slipping away, wondering if maybe Control was right. Maybe obeying wouldn’t be so bad. Maybe it would be good to just surrender, to let go, to become 619.

“NO!” Rarity shouted, or tried to, as her need to cum was denied at its peak yet again... The unicorn’s denials were starting to sound hollow, even to her, as the repetitions of arousal and denial chipped away at her resistance and unravelled the fabric of what made Rarity the mare that she was.

’Please help. Anypony, please save me,’ Rarity cried out in her thoughts. ’If anypony or anything can hear me. Please. I’ll do anything to get out of this.’

Another round of building orgasmic pressure built inside of the unicorn, and this time the mare had to concentrate on denying the will of Control. Of denying the pleasure it offered to her. If only she would obey, she would be allowed pleasure.

Did you really mean that? said a voice, shocking Rarity back to herself and she realized just how close that last cycle had been to completely undoing her will and sense of self.

’YES!’ Rarity yelled into the mental void. ’Unless you’re some figment of my imagination, brought on as my mind comes apart like a worn rag in the wind.’

I am real, and we have met before, my little pony, came the reply, in a voice like silk on steel.

’Discord? Is that you? Please, get me out of this, and I’ll… I’ll even push Tom around town for you,’ begged the unicorn, as she felt the fire inside of her being kindled to life yet again.

Discord is busy with his own plans, answered the voice, now carrying a rich feminine lilt to it. Your friends and I did battle once before, in a castle, in the Everfree forest.

’You—you’re the Nightmare!’ replied Rarity, in realization. ’You’re the thing that possessed Princess Luna.’

Indeed, and I am offering to possess you in order to free you from this thing that is going to turn you into a subservient slave, the Nightmare stated, and Rarity couldn’t tell if the shiver down her spine was dread of the demon speaking to her or desire as she was being driven toward her peak yet again, by the fiend that held her in its iron grip.

’What? No!’ Rarity grunted out in denial of both the demon within and without. Searing pain burned through her mind as the suit responded to her denial as it always had, but the Nightmare merely chuckled.

Refusal is not an option you have, unicorn, countered the dark spirit. Either you will fall to this… thing that holds you captive, and become a near mindless slave to the twisted desires of this Celestia, or you join with me and become a Nightmare to her plans and to the plans of anypony who would ever seek to chain you or deny you your rightful place.

’I would rather die than let myself be used as a vessel to destroy Equestria and bring harm to my friends. Which is exactly what you tried to do when you possessed Luna, or had you forgotten your vow of “the night will last forever”?’ was Rarity’s response, and as the bonfire was lit once more in her loins, she welcomed what it was going to bring to her.

Luna’s fury and outrage shaped us both. The will and desires of the pony I join with create the form of both our appearance and our actions. As will yours if you join with me. If you truly wish that Equestria and your friends remain unharmed, then that is how it shall be, was the response of the Nightmare, a touch of urgency now in its mental voice. Decide quickly now, for you have little time.

’Swear to me that you won’t make me hurt my friends, or Equestria,’ Rarity demanded, feeling the ocean of pleasure rising up to swamp her at long last.

I swear it. I swear that Nightmare Rarity will do no lasting harm to her friends or to the lands she lives in, even in self-defence, vowed the spirit, triumphant.

’Sadly, yours is the best offer I’ve had all day. I accept. What do I have to do?’ Rarity asked, choosing what she hoped was the lesser of two evils.

Open your mind to me, Rarity Belle, and accept my power, open your heart to me and receive my majesty, open your soul to the night and become OUR GLORY! cried the Nightmare with ecstatic joy as it took form in the waking world once again.

As one battle within came to an unexpected conclusion, a battle without was being rejoined. Four survivors of the morning’s sneak attack were taking refuge in a hidden nook of Twilight’s castle. A nook that did not appear on any plans and up until that morning had been known only to a certain maimed pegasus who had grudgingly begun to call the crystal edifice home.

“The Great and Powerful Trixie does not like this place, Dashiel,” the showmare and sworn Knight of Twilight stated, her nose crinkling in disgust. “It smells of cheap booze and wet pony. Where are we anyway?”

“Something the castle made for me a little after I first got here,” replied the war-torn reflection of Rainbow Dash. “I needed a place to store my wing where nopony could get at it, and a place I could… be by myself.”

“You mean get shit-faced drunk and bawl your face off where nopony could see or hear you, right?” Derpy asked, her maid uniform torn in a few strategic places to allow greater freedom of motion.

“What the fuck are you talking about?” swore Dashiel, rounding on the other pegasus, who responded by flaring her wings; which all present knew held an always surprising array of weaponry.

“The castle was a little slow in adding soundproofing to your hidey hole, and this is right above the linen closet,” Derpy replied, calming herself as she folded her wings back against her body.

“Oh, sorry,” Dashiel awkwardly apologized as she backed down.

“We should just surrender now. Control won’t hurt us if we submit,” suggested the fourth pony in the room, the mind-broken dimensional sister of Trixie Lulamoon, who would only answer to the name, “143.”

“You know we can’t do that sister,” Trixie said, pulling the unicorn against her in a comforting hug.

“143, can Control track your suit, or give commands to it?” Dashiel asked, causing the other two ponies to blink in shocked surprise.

All of them had been around 143 for months, to the point that the latex symbiote suit that was bound to her had faded from their awareness and had become just another part of the unusual pony. Trixie and Derpy both took a fresh look at the gleaming black suit, from the light swish of its secondary tail, along the flowing lines of energy that traced their way along 143’s body, to the gleaming silver control collar that was closely fitted to the mare's throat, and both had a chilling vision of themselves similarly bound and broken by the device.

“143’s conditioning makes 143 want to go to Control right now, but 143’s mind is stronger than it used to be, so 143 will stay with her sister. But, if 143 or her collar hears the voice of Control addressing 143, or if Control sends a command to all suits, then yes, Control can make 143 do whatever Control wants,” 143 confirmed, adding, as Dashiel’s face became grim, “are you going to kill 143 now? To protect the others?”

Both Derpy and Trixie tensed. Both of them were armed, and Trixie was even partially armored as well, but both of them knew just how deadly Dashiel could be. Dashiel could be a drunken, foul-mouthed mess at times, but when it came to fighting the rainbow tailed pegasus was as sharp as a razor capable of summoning a ruthless warrior's focus that was frightening to behold.

“No,” Dashiel stated, cocking a sardonic eyebrow at seeing the other two mares visibly relax. “If it gets to that, I’ll knock you out and leave you tied up in a closet or something.”

“Trixie knows a spell that can put you to sleep for awhile, sister. We can just let you sleep through everything,” Trixie supplied.

“How long does that spell last?” Dashiel asked with sudden intensity.

“About half an hour,” Trixie replied, trying not to wilt as the warrior mare went nose to nose with her. “If a pony is tired, they’ll keep sleeping once the spell is over though.”

“Huh,” responded Dashiel, who pulled herself up and away from Trixie and began pacing back and forth, muttering to herself slightly.

“What in the—” Trixie began, before being shushed by Derpy.

“Pegasus ponies think better when we’re moving,” Derpy said softly into Trixie’s ear. “It never seemed to work for me, but I bet Dashiel’s coming up with a plan.”

“Okay, here’s the plan,” Dashiel declared a few minutes later, the choice of words bringing a small smirk to Derpy’s muzzle. “Trixie, you distract Breaker with some smoke bombs, while me and Derpy hit her from either flank. Master Derpy, your Wing Chun is better than mine, so while you get in close, I’ll take the mid-range. Together we’ll—”

“Get slaughtered,” interjected Derpy. “This is an alicorn we’re going up against. An alicorn that’s expecting somepony to come at her, and who’s guarded by magical constructs. Remember what happened to Applejack, Rarity, and especially Roseluck?”

Everypony in the room shuddered at the memory of the blood curdling screams from the flower pony when one of the black constructs had pounced on her from above. Dashiel had been forced to hold Trixie back as the earth pony begged for help while struggling against her envelopment. The only thing more chilling had been when the captured pony had struggled to her hooves some twenty minutes later saying, “621 is a good pony. 621 will obey Control. A good pony is rewarded. 621 is a good pony.”

“Fair point,” Dashiel noted, beginning to pace up and down again. “Okay, so we either need more firepower or a better distraction than some smoke bombs, no offense Dame Trixie—”

“None taken,” Trixie slid in, a pleased smile replacing her frown at the reminder of her position of being Twilight's sworn knight.

“Okay, Plan B,” declared Dashiel, her eyes widening with excitement as she rounded on Trixie again. “I need you to put me to sleep.”

“What? Why?” Trixie demanded, while the others looked on in curiosity.

“The shield Breaker put around the castle keeps anything from getting in or out, including messages, right? But I bet it doesn’t stop dreams,” explained Dashiel.

“You serve the Dreamwalker,” 143 offered, before crouching back into Trixie’s shadow.

“Just like your sister works for Twilight, I work for Luna,” the blue pegasus confirmed. “I’m betting if Trixie puts me under, I can get a message to my boss and arrange for an alicorn diversion. Then we hit Breaker with everything we’ve got.”

“Trixie believes getting a message to the princesses is an excellent idea,” Trixie stated, strutting forward a pair of paces. “But your battle plan will only result in tragedy.”

“The mission is what’s important,” Dashiel fired back, opening the locker which held her magitech wing. The deadly length of feathered silver and steel sinews sent out glints of light, somehow looking eager to be used in deadly combat once more.

“We all know about ‘The Mission’, Dashiel,” Derpy stated, her wing trembling in the urge to put a comforting wing over the scar where once feather and bone had once been. “You remind the Twilight Guard about it every time you spar with them.”

“You promised Princess Luna that you would not throw your life away. That you would die only when she allowed you to,” Trixie reminded Dashiel.

“A mare’s gotta do, what a mare’s gotta do,” Dashiel replied, taking out her war wing and starting to check it over.

“We already decided that we can’t win if we just go charging in. And Trixie does not think it would matter how good our distractions are,” Trixie reasoned, putting a hoof onto Dashiel’s withers, causing the mare to pause in her checks and look at the former showmare. “What we need is a deception, not just a diversion. We need trickery, treachery and illusion. Things that Trixie, the Great and Powerful Knight of Twilight, has in abundance. You go talk to Luna, let Trixie take care of planning the show that shall be our victory over this Breaker pony.”

“Luna, I’ve never questioned your priorities when it comes to physical fighting, but really, taking a nap? Now?” Celestia asked, her amused tone belied by the restless shift of her hooves and the occasional lash of her ethereal tail.

“Dashiel needed to speak with me, and decided to use the dream realm to make contact,” Luna explained, getting up off the dirt road that led to Twilight’s castle. “As we suspected, it is the version of you from the world where Twilight first encountered those suits of hers that is to blame.”

“How did you know she was asleep?” Celestia asked, curious.

“When she agreed to swear fealty to me I placed an enchantment upon her that allows me to know her mental state at all times,” explained the lunar alicorn. “It was with her consent and has proven useful on occasion. And thou should not denigrate thy own martial ability. Thou didst quite well.”

When Dashiel’s first warning of, “Invasion. Alien dimension. Slavers” had reached the castle; it had taken Celestia less than five minutes to roust Luna from a sound sleep, muster every Royal Guard pony in the palace, and bring them all to Ponyville in a single mass teleport. The effort required for that feat of magic had dropped the senior alicorn in her tracks for minutes more as she recovered, every second of which had been begrudged and fretted over, despite knowing that Luna stood watchful guard over her, protecting Celestia with her own body.

Nor had the Princess of the Night been idle while she stood guard either. Taking command while Celestia lay insensible, Luna ordered the two hundred ponies her sister had assembled to lay siege to Twilight’s castle, surrounded as it was by a shielding globe of foreign magic that tasted almost like that of her beloved sister, but was just different enough to be recognizable.

Just as that was completed, some sort of midnight-hued thing passed out through the barrier of energy as if it wasn’t there, only to be intercepted by the blasts of at least three different unicorns. The magical beams of destruction had done nothing to deter the bed sheet sized entity in the slightest.

In fact, the energy had seemed to invigorate the thing, causing it to briefly grow and then split into two separate creatures. One of which had stooped like a hawk to drop on Lily Valley, wrapping itself around the mare from shoulder to hip, while the other dove on Luna herself, only to find itself swatted back whence it came by a tree that the lunar alicorn had employed like a giant club.

Guardponies had then leapt to the stricken mare’s assistance, trying to remove the clinging ooze as it enveloped and bound the flower mare within it’s clutches. Just as her head was being covered and her muzzle bound, Lily had just managed to gasp out, “It’s inside of me!”

As terrible as watching Lily Valley being made into a living ponyquinn of latex had been, the horror over her envelopment had been nothing compared to what had happened roughly thirty minutes later when the hood had pulled back on it’s own to reveal the face of a mare who had been fundamentally changed by her experience.

“625 will return to Control now. All ponies will submit to Control,” Lily Valley, now 625 had stated, before moving toward Celestia and Luna, only to be stopped by the spears of guardsponies pointed at her chest. “Follow 625 and submit to Control.”

625 had turned and walked back to Twilight's Castle, and no pony, not even the princesses, had been willing to try to stop her.

“Ranseur, report,” commanded Celestia, to one of her sergeants. “Is the evacuation complete?”

“We’ve just put the last civilians on the train, and it should be pulling out any minute now,” replied the guard, eyeing the golden-globed castle with wariness.

“What took so long?” Luna asked, adding, “It has taken most of the day to evacuate a few hundred ponies from a small town. Why the delay?”

“Ponyvillians are used to hunkering down when crazy things happen. A lot of them are really good at hiding from trouble and it took us awhile to find everypony,” Ranseur explained.

“Fair enough, carry on,” Luna replied, dismissing the pony before turning to her sister. “Dashiel intends to attack. She has a small force consisting of herself, Derpy and Trixie.”

“I sometimes question Twilight’s wisdom in bringing a pony like that home with her,” Celestia commented. “Dashiel’s first thought is always to attack. To solve a problem by driving a blade through it until it isn’t a problem anymore.”

“And that is why I have bound her to me,” Luna replied, continuing as her sister gave her a questioning look. “She reminds me of myself, back in the fighting pits, and we both know that Friendship and Harmony are not the solutions to every problem. Some problems must be solved with naked steel, and Dashiel will be the blade I set into such problems. And besides, it was not wisdom that caused Twilight to bring Dashiel back with her. It was compassion.”

“True enough. However, I don't think that three ponies, even led by one as capable as Dashiel, are going to be enough to take on what is essentially another me,” said Celestia, gazing toward the crystal edifice. “What else did they say?”

“Dashiel requests that we create as big of a diversion as possible in twenty-five minutes time,” Luna informed her sister. “She would not give me the details, but apparently they intend to use the diversion to make their attack.”

“As big as possible, eh? Well that settles it,” Celestia stated firmly. “I’m going in.”

“You?” Luna asked, shocked. “Sister. ‘Tia. Of the two of us, I am the better in the martial field, while your talents lie… “

“With bureaucracy and paperwork. With lying on a couch; my tail flagging and my eyes begging a stallion to mount me,” Celestia added, smiling kindly in response to Luna’s grimace of distaste.

“I would not have put it so bluntly,” Luna commented.

“But it is what Decius trained me for, and it is what this… version of me has been using to corrupt and enslave ponies with,” Celestia explained, taking a moment to draw a loving hoof along her sister’s jaw. “And of the two of us, even you will have to admit that I will be more able to withstand anything those suits can do to me.”

“You are right, sister. But I do not have to like it,” was all Luna could say in argument, ears drooping. “We could still attack frontally. Make a diversion that way.”

“Luna, you know that nothing diverts ones attention quite like getting somepony getting in your face and giving it a good slap,” Celestia responded, and Luna swore the look on her sister’s face was positively vulpine. “And besides, I’m looking forward to giving this Celestia an object lesson in what it really means to be in control.”

I hadn't initially planned for Nightmare Rarity to make an appearance, but when I asked my editor how far I should go with Rarity's corruption from the suit, their replay was, "You really like Nightmare Rarity, don't you?"

I do. I really do.

Next time my patrons choose this to be the second chapter of the month, there will be a battle... and a bonus chapter afterwards.

Every month my patrons get to vote on which story they would like to see me work on following my commissioned story. This month they voted for me to write the chapter you've just read.

If you want a vote on what I write, join my Patreon and for as little as a dollar a month you can cast your ballot for whichever story you would like to have me update.