> Two Birthdays
>  by ViTheDeer
> --------------------------------------------------------------------------

> Chapter 1
> --------------------------------------------------------------------------

Celestia circled the object, eyeing it up and down. She had no idea how it had appeared in the center of her bedchambers, especially since the size of it made made it seem impossible to have even fit through her doors. Even if somepony had been able to open them silently without waking her, dragged the heavy object through them, and then close them just as stealthily, that is. Even if that pony had been somehow able to slip past her ever vigilant guards, and her magical alarms…
On her third circuit around the structure, nearly twice her own height, Celestia spotted something attached to the bottom. Closer inspection revealed it to be a folded note, which she immediately opened and read:

“Dear Princess Celestia, 
HAPPY BIRTHDAY!!! 
Love, 
Everypony in Ponyville”

And, below that, in a smaller script:

“Actually, I didn't tell anypony else that I was making this, because I wanted it to be a surprise and you know how Twilight loves to tell you everything and that would have ruined the surprise and you know how Twilight hates to keep a secret anyway and Applejack is just as bad I guess that's why they call her the Element of Honesty or at least they used to before the tree ate up our necklaces does that mean I'm not the Element of Laughter anymore because I still love to laugh and I don't think that I should stop laughing just because some big meany-pants tried to steal all the magic but anyway I hope you liked it it's my famous Marzipan Mascarpone Meringue Madness and it took me all day to make it but don't tell the others I wouldn't want them to be sad in case they forgot to get you anything that's why I said this was from everypony except then I told you it wasn't Oh can you forget I said that? Anyway, Happy Birthday!”
Celestia blinked. She wasn't sure how all those words had fit into the small space at the bottom of the card. At least now she knew who was responsible for the towering mass of frosting and cake that stood before her.
She circled it once more, letting herself appreciate it now that her worries had been abated. She wasn't sure how the pink one had known it was her birthday, as it wasn't a date she made a habit of sharing. She knew that, if her birthday was common knowledge, it would certainly become a national holiday. She really didn't need all that fuss made over her, not when there were much worthier causes to celebrate. That, and she'd also have to admit just how many birthdays she'd seen. That number was higher than she cared to admit. By several decimal places.
That said, there had been historians and astrologers who had claimed to have worked out what day she was born on in the past. Most of the estimates were off by a wide margin, but a few had actually hit the mark. She doubted that Pinkie was terribly well versed in the study of the stars and celestial bodies. She supposed that, like her Pinkie Sense, knowing when ponies' birthdays were was just one of those things that made Pinkie, well, Pinkie.
A small smile appeared on her face. The smell of chocolate cake and vanilla frosting was enticing, nearly intoxicating. Cake had always been a weakness of hers, and this one was truly a masterpiece. She knew she couldn't possibly eat the entire confection by herself, and vowed to invite her guards – and, indeed, anypony who wanted some – to help her finish the delightful dessert surprise. She’d come up with some excuse for why she had a two-story chocolate cake first, of course! 
Licking her lips, she turned to her bedside table, where the tray with the remains of her dinner from the previous night still lay. Of course, she thought to herself as she levitated a small knife off the platter, she certainly could sneak a slice off for herself before giving the rest away. 
She sized up the scrumptious sculpture, trying to determine the best angle of attack to maximize the frosting proportion while not detracting from the overall symmetry, when a faint buzzing sound made itself known in the back of her mind. Her ear twitched involuntarily, and it took her a second to realize that the sound was that of one of her magical wards being tripped. Perhaps a delayed reaction from Pinkie’s earlier intrusion? She’d have to get that looked at. 
Her ear twitched again as she heard another sound. It rapidly increased in volume, and seemed to draw closer.
She turned her head just in time to hear a loud crash. The clatter was accompanied by a blur of purple tumbling through her window. The blur coalesced into a ball that rolled across her floor. Celestia's eyes went wide as she realized, a fraction of a second too late, that the feathered ball of tangled limbs' trajectory was headed for the empty space at the center of her chambers. 
Or rather, what would have been empty space any other time. The space that was currently being occupied by a large, chocolate confection. 
The cake exploded in every direction, sending fondant and sugar flower blossoms everywhere. Chocolate and frosting coated every surface of the room, every wall, even the ceiling. In the center of the calamity, two figures stood,  both coated in sugary dessert. And both were, as chance would have it, princesses of Equestria.
“P-p-princess Celestia! I'm s-s-so sorry! I was hoping I'd get here before Pinkie… But I'm too late! I'm so, so, so, so sorry!” Twilight was practically groveling, her face flushed. “I didn't even know it was your birthday! And I tried to tell Pinkie that you don't like a big fuss, but she said that I was being silly, and that everypony should get a cake for their birthday, and I asked her what she did and she said she was going to surprise you and… and…”
Twilight's voice trailed off, and her eyes grew wider as she took in the state of the room around her. Her cheeks grew even brighter, her eyes darting every which way except in the direction of her mentor and ruler.
“I got here as fast as I could  I thought… Thought I could hide it or something… Oh, please don't be angry at her!”
“My faithful student, why would I be angry?”
Twilight looked up, her brow slightly creased. She looked like a filly who had just been caught with her hoof in the cookie jar. Icing clung to her fur in tufts, and her usually impeccably tidy mane was sticking up at odd angles. She looked adorable and, Celestia thought in spite of the chaos, slightly delectable.
Twilight must have interpreted her mentor's silence as one of disapproval, as she had started visibly tremoring.
Celestia affected a pout. “Twilight Sparkle, just look at yourself! Is that any way to present yourself, a princess of Equestria?” 
Twilight's head hung low. “No, Princess.”
Celestia took a slow, deliberate step forward, closing nearly half the distance between the two alicorns.
“It will surely take forever to get all this cake out of your coat. It's really gone everywhere, hasn't it?” 
Twilight nodded slowly. She looked so sorrowful and dejected. Something about the way she held her wings, feathers clumping together with chocolate cake, was somehow adorable. Celestia found herself licking her lips at the sight of her student, and she wasn't sure whether it was the thought of her beautiful birthday cake spread all over the younger pony's body, or the realization that they were standing nearly cheek to cheek, inches from Celestia's large and inviting bed. 
Not that she had ever pictured this scenario in her head before. A pony of her royal stature certainly never succumbed to such base desires. And, even if they did, it was inconceivable that they would involve a student, one in whose esteem she was who held with such regard.
Celestia reminded herself of all these facts, hoping it would detract her attention away from the damp sensation beginning to increase between her legs. 
“Twilight, I know that, as a unicorn, you had been raised without the benefit of some of the more basic lessons that pegasi learn as foals.” 
Yes, become the teacher once more. Distance yourself from her.
“For instance,” oh heavens, what am I doing? “Do you know the best way to clean your new feathers?” 
Twilight opened her mouth as though to speak, but no words came out. She closed it again, shaking her head. 
“Soap and water will not do, they will only cause the feathers to fray.” Celestia learned in closed, her muzzle nearly touching Twilight's outstretched wing. “The far better solution is to… Well, here, allow me to demonstrate.”
Slowly, Celestia extended her long tongue. She felt a tremble make its way down her spine. as the gap between her tongue and Twilight's chocolate-coated primaries grew smaller and smaller. 
She chastised herself for body's schoolfilly-like reaction, but was cut off mid-thought as she registered Twilight's scent for the first time. 
It was sugary-sweet, full of chocolate and hints of vanilla. Celestia inhaled deeply as she slid her tongue along the feather. There was something else beneath the cake scent, something dark and enticing. It filled her senses, overwhelming her and causing the dampness she had nearly put out of mind to grow ever stronger.
Reaching the end of the feather her tongue had been caressing, she withdrew her tongue and swallowed. Celestia wasn't sure if it was a testament to Pinkie's skill as a baker, or to the unique aroma that her favorite student added to the mixture, but that small mouthful was easily the most tantalizingly delicious taste she had ever experienced. She felt her cheeks grow red as the flavor seemed to spread down her throat and into her belly. And beyond.
Twilight's face wore an expression of complete befuddlement. She seemed unsure of how to handle the sudden increase in intimacy with her teacher, seemingly torn between a desire to run and hide, and an need to take notes.
Celestia wanted to tell her it was all a joke, just a foalish prank. But every time she opened her mouth, all that emerged was her tongue. It found another dirtied feather, and another mouthful of cake and frosting. She felt no longer in control of her own body. The heat spreading from her belly and into her limbs was in control now. She could no more resist the pull than the sun could resist her willing it to rise every morning.
After a few moments of Celestia's delicate attentions, Twilight's muscles relaxed. She stretched her wing out wide, allowing the feathers to spread for her teacher to better reach. The teacher, in turn, lovingly caressed every feather from quill to tip and back again. Twilight's earlier resistance melted away. Celestia even thought she could hear the barest hints of a gasp every time her tongue brushed against the strong wing muscles hidden beneath the feathery cloak.
Within moments, Celestia had preened every feather on Twilight's wing, licking up every crumb of cake and speck of frosting. Twilight was already holding her second wing aloft, ready for her teacher to attend to it as well. The corners of Celestia's lips curled up, and her eye glistened, as she shifted her attention. Rather than circling to the younger pony's other side, she took advantage of her larger stature. Lapping at the final feather, Celestia drew her tongue down the muscles of Twilight's wing. Rather than lifting her tongue from her student's warm flesh, she proceeded to drag it along the small of the pony's back before working back up the opposite wing. Twilight let out a surprised yelp as Celestia's warm, moist tongue crossed her spine. The sound made Celestia grin. It also made her shift her hind legs, between which it felt as though somepony had lit a fire.
The wing which Celestia had begun with borne the brunt of the impact with the cake, so the second was disappointingly quicker to clean. Celestia made sure that no attention was lost, however. She tended to every feather just as lovingly as she had those on the first wing. More so, perhaps. In the absence of confectionary, Twilight's own taste was much more intense and irresistible. 
Celestia had all but lost all control of her functions. It was almost as though the young princess had cast a spell on her, so alluring was her taste, her scent, the soft texture of every tiny feather against her lips and tongue.
When it became apparent that she could no longer use the excuse of grooming to explain her mouth's activities, Celestia pulled back. She was now standing so close to Twilight that the young alicorn’s skin felt flaming hot against her own. Flaming hot, and still covered in sticky frosting, Celestia realized.
She caught Twilight's eye and smiled, a loving, motherly smile. At least, she hoped it appeared motherly. She hoped that the tendrils of lust that were enveloping her heart hadn't touched her face. 
Judging by Twilight's expression, they had not. She smiled back and let out a feeble “thank you.” She could see Twilight’s cheeks were bright red, however. She wondered if the young alicorn’s face was the only place blood was flowing to.
“You are far from clean yet, my dear Twilight. Here, let me tend to the rest of your coat.”
Before Twilight could protest, Celestia's tongue was already upon her. Like a cat bathing her kitten, Celestia licked Twilight's coat from top to bottom. Every lick brought a new mix of flavors to Celestia's mouth. As she reached the top of Twilight's head, she felt her tongue meet something hard. Very hard, and long, and warm to the touch.
Celestia slowly dragged her tongue over the young alicorn's horn, savoring every inch of its hardness. She could see it was glowing faintly, and she could only imagine how her own must look. It could be difficult to keep control over one’s magic when one's senses were full of other pleasures, after all. The moan that reached Celestia's ears as she reached the tip of Twilight's horn told her that the young princess was very much enjoying the experience.
The frosting had worked its way into the spiral ridges of Twilight's horn somehow. It resisted Celestia’s tongue's attempts to work it out. She pressed her lips around the tip of Twilight's horn, pursing them as though in a lover's kiss. Then, in a single deliberate motion, she took Twilight's horn into her mouth.
She danced her tongue around the her horn as she swallowed ever more of it. Every inch was a sweet treat, growing ever sweeter as she took ever more of it into her mouth. She could feel the tip in the back of her throat by the time her lips finally brushed the soft strands of Twilight's mane. She withdrew the horn just as slowly, sucking gently as she did to loosen every speck of frosting. The tip finally emerged with a soft “pop”, and Celestia licked her lips.
She could feel Twilight's breath hot and ragged against her leg, Celestia's own breathing had begun trying to keep pace with her heartbeat, which in turn was racing faster than a hummingbird's wings.
Celestia planted a small kiss on the tip of Twilight's horn, and surveyed her work. The young princess was clean, for the most part. Her coat was still clumped in a few spots, though perhaps more due to Celestia's saliva than to the cake frosting. Still, there was one area where Celestia had deliberately avoided attending to.
Twilight's cheeks were bright red, but her expression was one of serene bliss. Heat radiated off her body, and her scent filled the air. Celestia planted another kiss on the young princess, this time just to the side of her horn. That kiss led to another, and another; in her mane, on her cheek, on the tip of her muzzle. Twilight's mouth opened slightly to meet her, and Celestia took it eagerly. Their lips enfolded one another. Twilight's kiss was tentative, curious, inexperienced. Celestia guided her lips and tongue with her own, once again playing the teacher to Twilight's student.
If she had thought the cake sweet, Twilight's lips were beyond delectable. She feared that no dessert would ever satisfy her again, so long as she had the taste of Twilight's luscious lips in her memory. She took hungrily and insatiably from her student’s mouth, breaking off only when the dizziness that had rushed to her head threatened to overwhelm her and send her toppling.
Twilight looked deep into her eyes. A longing desire played across her face. Her lip jutted out in the tiniest pout that made Celestia's heart melt. The expression, which on a pony such as Rarity's face might have looked coy and practiced, was nothing but pure and precious on the young alicorn.
Catching her breath, her lungs full of Twilight's perfume, Celestia once again brought her tongue to the younger pony's skin. She dragged it slowly along her cheek, down her neck, her withers and sides. The chocolate and frosting flavor grew stronger as she reached the area she had skipped before. It reached a peak intensity as Celestia's tongue met Twilight's cutie mark. She wanted to pause there, but she licked onward. The cake and frosting’s sweetness was replaced by another altogether as she reached her tongue’s ultimate goal.
Celestia’ heart leapt as her student lifted her tail to one side. A meek voice inside her head once again protested, but it was quickly drowned out by her intense lust and desire. Celestia's own nethers felt as though a dam had burst between them, and she could see Twilight had had a similar response. Celestia had seen her student’s marehood before – After all, it was difficult to avoid seeing a pony's sex in everyday life when so few of them wore clothes – but it was one thing to catch a glimpse of it beneath Twilight's perfectly groomed tail. It was quite another to have it fill her senses this way, glistening and winking.
Celestia wanted to tease her, to slowly circle her way around Twilight's marehood, licking one thigh and then the other, flicking her tongue over her opening ever so tantalizingly.
But all thought of foreplay abandoned Celestia as she felt the heat coming in waves off the mare's sex. She smelled the wetness, so full of Twilight's scent and so much more. She was only vaguely aware of Twilight's moans. They came to her ears in waves, distant but insistent, as she pressed her tongue against Twilight's folds. They parted easily, glistening and hot. Celestia wasted no time in exploring the new territory she had burgeoned into. Her tongue curled and circled around folds and mounds. Twilight tasted of sugar and butter fudge. Celestia didn't think she could bear it much longer, she had to be deeper inside of her student. She pressed her muzzle against Twilight's sex and probed with her tongue as deeply as she could go. Twilight was tight, and Celestia could feel her own folds begin to drip at the sensation of her student squeezing around her own sensitive tongue. Reaching out with a hoof, she gently pressed it against where Twilight's folds met her belly. She began rubbing in a slow circular motion as her tongue darted in and out. Twilight's moans increased in volume and in desperation. Celestia could even feel her young student begin to buck her hips against her muzzle. This only drove Celestia to increase the forcefulness of her tongue's thrusts.
With a gentle touch of the tip of her hoof, Celestia found her student's sensitive nub. A slightly harder press was all it took to make Twilight's breath catch in her throat. Twilight wasn't bucking anymore. Instead, all her weight pressed against Celestia’s muzzle. It felt as as though the younger pony’s legs had given out altogether. Celestia let the loss of support press her student's folds harder around her own muzzle, and began flicking her tongue over her nub. 
She attacked it from both sides, with her hoof and her tongue. Twilight’s moans had been replaced by guttural, primal grunts of pleasure. It was all Celestia could do not to take her hoof to her own burning sex, but she denied herself the satisfaction. Instead, she devoted all her energy to her student. She lapped at Twilight's clit, sucking it gently before attacking it with her hoof once more. Her tongue made wide circles as she played with her student's limits, darting in and out of her opening before returning to caress her clit.
A violent shudder passed through the young alicorn's body, and she let out a loud cry. The wetness that had coated Celestia's muzzle increased suddenly, and she could feel Twilight’s opening spasm around her thrusting tongue. 
Twilight's legs, which had only just began to carry her own weight once again, gave out once more. Twilight rolled away from her teacher and onto her side. Her wings were still solidly erect against the marble floor, and her and face was burning with redness.
But Celestia wasn't finished with her yet. If Celestia had one weakness… well, it was cake, she admitted to herself. But if she had a second weakness, it was seeing the look on her partner's face just after she had brought them to climax.
Without giving Twilight a moment to catch her breath, Celestia dove in again. She lapped at her student's folds hungrily, fiercely. She could feel her partner squirm as she brought Twilight closer to the edge once again. Celestia placed a hoof on Twilight's hips, holding her in place. She attacked Twilight's sex with lashing licks and deep sucking kisses. She could feel Twilight's muscles tense again as she let out another cry of ecstasy, but Celestia didn't let up. Instead, she placed her lips around Twilight's clit and began sucking on it. She sucked on it like she would a piece of delicious candy. She gently bobbed her head as her lips encircled the swollen nub. She suckled on it hard, from base to tip, with the same fervor she had shown Twilight’s horn earlier.
Twilight's cry increased by an order of magnitude before abruptly stopping. Looking up, Celestia could see that Twilight had clamped her mouth around the closest thing she could find, which happened to be the remains of the bottom layer of cake. The chocolate treat served as an excellent gag. Celestia took the opportunity to increase the vigor of her mouth’s attacks.
Celestia’s mouth let go of Twilight's clit, only to have it be replaced by her hoof. Celestia’s horn lit up brightly as she added her magic to the mix. She let her magic flow over Twilight's rump, caressing it with a thousand tiny tendrils. Then she allowed them to coalesce just outside Twilight's opening.
Without further pause, Celestia forced her magic inside of Twilight's sex. She filled her with thousands of tiny strands of thrusting, writhing, magical tentacles. The air smelled of ozone and sweat and chocolate and the unmistakable, indescribable scent of Twilight Sparkle. Stuffed with cake as it was, Twilight's screams didn't make it past her mouth. Instead. they reverberated in her chest, causing her whole body to shake. Celestia could feel herself approaching her own climax. She felt the wave of pleasure wash over her as she drove her magic deeper and deeper and harder and faster into Twilight's body. 
Her vision exploded with light as the orgasm washed over her. All she could feel was the hot, burning sensation of Twilight's sex on her muzzle and hoof. All she could hear were her own screams of ecstasy. Or perhaps they were Twilight's, she couldn't be sure. 
Feeling suddenly drained, she collapsed on top of her student. Twilight was already panting and shaking in the afterglow of her many orgasms. Celestia licked at her own muzzle, which was now coated in a salty-sweet icing of its own. The sweet wetness had also dripped down the inside of her legs. She covered them with her tail as the breeze began to chill her soaking limbs. Together they lay, master and student, holding each others’ exhausted bodies close to their own.
Curling into her teacher's limbs, Twilight reached up to kiss Celestia's lips, gently and still trembling slightly. Celestia returned the kiss in kind, and covered both of them with a long, graceful wing.
Celestia felt like the room was spinning. She could feel Twilight's heart beat against her chest, and could hear her breathing begin to slow and deepen. Clutching her tight, Celestia closed her own eyes, and rested her chin on her student's neck.

Celestia had almost drifted off to her sister’s domain, when a loud bang startled her back into the waking world.
Opening her eyes, she saw that the large doors into her chamber had been slammed open. Looking at who had been impertinent enough to disturb her and her young lover, she had to blink to clear her vision.
She blinked again, certain she was seeing double. There, in the doorway, with a determined glare on her face, was her young student, Twilight Sparkle.
> Chapter 2
> --------------------------------------------------------------------------

“What in the name of all that is sacred is going on here?” Twilight looked at her teacher, then at the purple form curled up in the Princess' legs, then back to Celestia. She could feel her mouth hanging open, and firmly shut it. A moment passed in stunned silence.
“So, is somepony going to explain to me why there is another me here? And why you two are covered in what I can only hope is chocolate cake?”
The other Twilight lifted her head and stared directly into Twilight's eyes. As she watched, she saw the pupils that mirrored her own shimmer and shift. They narrowed into twin slits, color changing from purple to green. The figure's lips curled up in a smile.
A sudden flash of green light filled the room. The Twilight that had been cuddled up against Celestia disappeared. In her place, a tall creature with a shiny black carapace stood. Holes permeated her legs and horn, and a cackling laugh emerged from a mouth full of razor-sharp teeth.
“Chrysalis!” Celestia's voice was boiling with rage. “You dare enter my castle, thinking you could pose as my student?”
Chrysalis' face affected a lopsided grin. “More than simply pose as, I dare say. You never questioned her identity for a second. Why, I barely even had to use my mind control powers on you at all, so eager were you to give your love to your precious princess pupil!”
Twilight blinked, looking from Princess to Queen and back again. “Princess Celestia, what does she mean by…”
Before she could finish her sentence, Twilight felt a sticky substance cover her muzzle. She tried to close her mouth, but found she couldn't. Some sort of slimy, adhesive material filled her mouth and began to harden around her muzzle by the second. Her eyes went wide as she saw the insect-like form flash the same, green material into being around her mentor's muzzle. 
Twilight tried to call out in protest, but only found herself letting out a throaty cry. The green material cut off any word she might have spoken.
The changeling began to cackle. She stalked towards Twilight, still standing transfixed in the doorway. Twilight turned to run, but found that her legs were immobile. Looking down, heart heart sank as she saw she was held in place by the same substance that kept her mouth gagged.
Desperate, she lashed out with her magic, only to be met with a flash of green that temporarily blinded her. When her vision cleared, she felt a substance coating her horn. Somehow, her magic had been contained. No matter how hard she struggled, she couldn't penetrate the ethereal barrier with her power.
She felt her breath coming more quickly. She fought back the urge to panic. She tried to stretch her wings, they were pinned to her sides, useless.
Desperate, she looked to Celestia for help. She saw that her mentor had also been bound and gagged by the same green material that kept Twilight immobile. She could only look helplessly into her Princesses’ eyes as she struggled against the Queen’s bonds.
Chrysalis began to circle them, looking them up and down. 
“I knew I was thinking too small when I went after your brother. After all, if feasting off of his love was enough to bring down the ruler of Equestria, how much more powerful would I be if I fed on the Princess herself?” Another loud laugh rang out, as the changeling tested the bonds that held Twilight with her hole-ridden hoof.
“But how to get that delicious love out of her? How to make her fall to my whims? My first instinct was to go after her sister. But, as I was stalking her one night, this little one happened to fly into Canterlot.”
She began poking at Celestia's bonds as she spoke, adding to them in one or two places until Celestia could barely twitch a muscle. The large alicorn's sides heaved in labored breath, but other than that she was held fast.
“I could smell your love for this one from halfway across Canterlot, dear Celestia. You should know better than to wear your heart on your sleeve so. Others might take advantage of that, after all.” She grinned again, then drew back a hoof and gave Celestia a firm slap across her cheek. Celestia's face bore no reaction save for a growing redness where the hoof had made contact.
“And here I am once again. Once again more powerful than Celestia. More powerful than her student, too, without her friends here to save her. I am the rightful ruler of this nation, and soon all will bow down to me!”
Chrysalis cackled maniacally at her own pronouncement. Twilight's mind raced as to how she could escape her predicament and save the princess. Chrysalis was right about one thing, her friends had no idea she was here. After all, the whole point of her coming was to keep Pinkie from embarrassing herself, and the last thing she had needed was for word of that to spread. 
Think, Twilight. Think!
Chrysalis lowered her gaze to look directly at Twilight, and for a terrified moment she wondered if the changeling could read her thoughts. But the dark figure merely continued her monologue.
“Ah, but one thing remains for me to attend to. After all, what is a Queen without subjects? And I fear that, after my last attempt to claim my rightful place as ruler, you,” her eyes narrowed as her gaze at Twilight intensified, “left me without a brood.”
Chrysalis broke the gaze and began stalking around the two princesses once again. Her tail was swaying with every step, and Twilight couldn't help but catch a glance at what the base of the tail concealed. 
“But, thanks to your little indiscretion with your student, I've feasted on more than enough love to create another brood of loyal followers. And, as it turns out, you have not quite outlived your usefulness.”
She directed the words at Celestia, her tail swinging even more wildly as she spoke. Twilight could see something moving there, something shifting, elongating. In a sickening motion, a shining, glistening shaft appeared. It was almost phallic, yet at the same time twisted and wrong creature creature – green and slightly translucent. Twilight thought she could almost see something moving inside of it. It turned her stomach to watch, but she couldn't look away. She hadn't even noticed that the queen had ceased her tail's swaying, and was now holding it high and to the side, as if displaying her organ proudly for Twilight's gaze.
“You see, my eggs need a warm, fertile place to hatch. And, as it so happens, I now have not one, but two very fertile alicorns at my disposal to serve as my broodmares.” With this, Chrysalis stepped towards the helpless Celestia. Twilight could see the alicorn struggle against her bonds, her eyes wide in fear. All her struggling did was increase the width of Chrysalis’ smile. The changeling placed a warm, wet kiss on the alicorn's cheek, then dragged her slithering tongue along the side of her neck.
Twilight watched helplessly as the black, shimmering figure made her way to the far end of her beloved princess. She tried to look away, but found she was somehow transfixed, forced to watch. The changeling placed two hooves on her mentor's back, and proceeded to mount her as a stallion would a mare.
Chrysalis began to chortle once more as she thrusted against Celestia's hindquarters. Faster and harder she bucked the princess. Celestia was immobile, and unable to make the slightest protest. In her eyes, Twilight could see nothing but horror and defiance.
Chrysalis' hideous laughter mutated into moans of pleasure. The slick sounds of the changeling's organ inside of Celestia's marehood brought bile to Twilight's throat. It was all she could do to hold back the waves of nausea that threatened to overwhelm her as she watched her beloved teacher being raped by the horrific figure.
No, not horrific. Fascinating. One might even say, beautiful.
Twilight's revulsion left her, and she saw everything much more clearly. It wasn't terrible, it was beautiful. 
All she want was for her children to be born strong and plentiful. What more natural thing could there be?
She watched as the radiant figure deposited the last of her eggs into the unwilling host. She could see the glistening of the Queen's carapace as she left the white alicorn, and then sauntered her way towards Twilight. The Queen’s horn was glowing, a beautiful green glow that seemed to fill Twilight’s vision and envelop her very soul in its warm embrace.
She hoped her eyes could show her willingness to be a part of this miracle of life; hoped her Queen would not pass her over in favor of a more worthy host. She could feel her nethers dripping with anticipation, her blood pounding in her ears as her Queen drew closer. She didn't feel the restraints anymore, merely the comforting protection of her cocoon. She felt her marehood winking, desperately hoping to catch Her Majesty's eye.
When her Queen finally did cast a gaze her way, the mere sensation of Her eyes' touch almost brought her to the edge of orgasm. She needed to feel Her inside of her, to feel Her eggs filling her womb, to be the one to bring Her children to life. Even if that meant having to sacrifice herself, there could be no greater purpose than to serve Her and Her children.
The Queen's hoof felt like fire as it touched her flank. She shuddered as she felt Her cold, hard belly brush against her back. Any moment now, she knew, her Queen would bestow upon her the greatest honor any mare could hope to obtain. She could no longer see Her as She lifted Herself on top of the alicorn's back. She spared a glance towards the white alicorn, now crumpled and exhausted where her Queen’s cocoon held her fast. She would always hate the other alicorn for having been the first chosen to bear the Queen's spawn. She was full of jealousy and hatred for the white alicorn for having been chosen for the highest of all honors.
All thoughts of being second left her as she felt her Queen entering her. Her sex parted to make way for the Queen’s cold, hard organ. It penetrated her deeply, tearing and pressing and forcing its way deep inside of her. Waves of pleasure accompanied the pain of the organ filling her sex. Her gag was the only thing preventing her from screaming in pure ecstasy, as her Queen's touch brought her to climax. Already shuddering from the force of the orgasm, she found herself being pressed to even further limits of pleasure as she felt the Queen's eggs sliding inside of her. Little cold marbles entered her womb, each one the promise of a tiny life so much more worthy than her own. It was all she could to not to pass out from the sheer joy of that knowledge, along with the wave after wave of pure electricity that danced along her spine to every single nerve ending in her body.
She felt her queen thrusting, her unyielding organ probing her insides. With each thrust, another batch of the tiny, cold eggs were inserted into her body. She felt her womb filling, her insides bloating with the promise of so many young lives. Her eyes flooded with tears at the knowledge that she would make her Queen's rule a bountiful and mighty one. 
As her Queen deposited her last egg and left her body cold and alone, yet full of her young ones, it was all she could do to keep from weeping. She took small comfort at the feeling of fullness in her belly, and could feel the eggs settling into place in her fertile womb. 

Chrysalis surveyed the scene. Two princesses of Equestria had fallen to her whim. Two more would follow shortly. She had already bested the Princess of Love. The Princess of the Night, powerful though she may have once been, would be no match to the power she had collected from the love between these two. 
She strode to the open window, casting a gaze over her new kingdom. 
Today was a good day.