Under a Golden Hoof

Twilight Sparkle gave a loud moan though the bit gag in her mouth as a gold covered hoof gently ran down her spine, the metal cold against her hot skin.
Her fore-hooves were pulled taught and up, above her head, by iron chains attached to iron manacles. This caused her to put most of her weight on her rear-hooves, which were currently spread just slightly past shoulder width, locked open by a dull iron rod attached to another set of manacles. The outside of each lower manacle were tied with short strips of brown leather to sturdy eye-bolts driven into the stone floor.
The position gave her an even balance but didn't allow for any kind of privacy.

Her tail had been carefully braided with a deep red silk rope and pulled up along her back, revealing all of her most intimate parts from behind. The trailing end of the rope was loosely tired around her throat in a sort of noose. She could lower her tail, but then she would only wind up choking herself until she raised it again and loosened the knot.
The gold shod hoof gently rubs above the base of the bound tail, getting a deeper moan from the purple mare and a slight increase to the glow from the base of her horn. Her magic was being blocked by a simple looking dull silver ring about three fourths of the way down her horn.

The air was heavy with the scent of arousal and every few seconds there was a wet plick sound as clear liquid dripped from between Twilight's thighs to the stone floor, adding to the quickly growing puddle already there.
She arches her back some, ever so slightly thrusting her rear towards the owner of the hoof and turns her head to the side a little, pulling on the chains hanging from the ceiling to take a little weight off her back legs for just a moment. She had a blindfold over her eyes so she couldn't see what was going on, but it didn't matter much because the glow from her horn was the brightest light in the room anyways, low candles here and there as well as the very soft pure white glow from the only other pony in the room.

The hoof leaves her body and Twilight can't stop the small whine of disappointment that comes from her throat when it does. Her whine is met with a small light laugh, one with the sound of fine ceramic bells on a crisp morning. A sound so pure and enchanting any who heard it couldn't help but want to hear it more and more.

Princess Celestia moves closer behind Twilight, wrapping her front legs around the smaller mare, rubbing her barrel against the bound tail. She leans down to nibble on one of the purple ears, it trying to flick away from the assault but not being successful.
She rubs her gold shod hooves over Twilight's barrel, getting another cute moan from her toy as well as more plicks from below. The horn glow also increases a little more, but again doesn't move past the ring.

Moving her mouth away from the ear the solar princess angles her head to muzzle at the base of the purple horn. The sensation causes the glow to nearly double in intensity and the pony said horn was attached to push up hard with her back legs and lets out a deep, loud moan, one filled with lust.

The sound of Twilight's juices falling was an almost constant plick-plick-plick now, at least two drops a second if not more. A burning need sat in Twilight's belly, something which she could do almost nothing about on her own. The thought of that just made it grow a little bit more.

Celestia licks the base of Twilight's horn, getting another immediate, strong, reaction, before she pulls her mouth away, again getting a disappointed whine in response. She runs her hooves down to Twilight's belly, just above her pert nipples.
The two nubs stood out clearly, so dark a purple to be almost black against the, by comparison, lighter purple of her fur. Celestia playfully toys with both of them, her cold metal hoof caps almost painful against them to Twilight. The small purple unicorn was shaking with need, her body pressed back hard against her mentor and mistress.

Instead of catering to that need though Celestia drops her hooves away from Twilight, also taking a step back and away, removing her warmth from the bound pony and can't help but grin at getting another whine of disappointment. She never really did tire of that sound when Twilight made it under these circumstances, but this time she cuts the whine short by slapping her right hoof against Twilight's right cutie-mark, the smack of metal on flesh ringing out clean in the stone room.
The metal digs in hard against the soft, yielding, flesh, pulling back and leaving it red and angry under the fur.
Twilight's cry of pain was of course muffled by the bit gag, as well as the moan of pleasure that followed as the warmth of the hit eased the pain. And even though she knew it was coming the hard slap to her left cutie-mark still caught her by surprise and made her cry out in pain once again, body shaking in delight once the warm glow started to spread over her flank.

After the second slap Celestia walks around to be in front of her captive, her metal caped hooves somehow not making a sound as she does. She leans forward to nibble on an ear again, but only for a moment this time.
Stepping back again she carefully judges her distance and lowers her head, brushing the rather sharp tip of her horn against Twilight's right cheek.
The unicorn immediately went still, her lower body still giving minor, uncontrollable, shakes from her ever growing arousal but she keeps her upper body, and especially her face, as still as she can though sheer force of will.
The white horn is lightly drawn down her cheek, not enough to draw any blood but just enough to leave a light scratch that ignites the nerves in glorious pain. It flared like a paper cut, hissing and biting at Twilight's mind.
The pain didn't last long though, replaced by the sensation of warm soft lips pressed against her flesh, Celestia kissing the pain away just as quickly as she had caused it.
Her lips move from the scratch over to the gag, kissing around it, forcing her tongue into Twilight's mouth to play for a few, so tortuously few, moments before she pulled back.

There was no longer a plick-plick-plick sound coming from under Twilight, instead it had been replaced by a constant if thin stream of fluids hitting the floor. Her whole body shook again, a low sound somewhat like a groan and somewhat like a moan coming from her throat.

Celestia steps back again, enough so that Twilight leaned forward towards her, towards the warmth of her lover so easily felt in the cold room. And as the princess moved even further away that warmth diminished until it was gone completely, leaving Twilight alone in the cold and the dark.

She was bound, all of her hooves and her mouth and especially her magic. She had no means what-so-ever of self-release, be it from said bindings or the growing, burning hot need between her haunches.
Now, Twilight knew, logically, that Celestia hadn't really left her alone, that she was still in the room, watching.
Celestia was always watching after all.
But the logical part of her brain had called a hiatus somewhere around the second hour of this session and gone somewhere else for the remainder.
So without her logic to defend her Twilight could feel fear and panic start to set in. For a herd species there was nothing more frightening than the thought of being alone and vulnerable. And without that familiar comforting warmth she was feeling more and more alone every second as she took deep, ragged breaths.

Now, her breathing had already been fast because of arousal; short pants through her nose and around the bit in her mouth. And her heart rate was also elevated to provide blood flow to certain lower regions of her body. Right now her heart was a swift drumbeat in her ears, one rapidly increasing in tempo in the otherwise silent room.
She jerked her head left and right, as if searching for salvation, but the blind fold prevented any real hope of seeing anything at all.

Just as that irrational bubbling panic started to rise from her belly to her chest and grab ahold of her heart she was engulfed by an all-encompassing warmth, soft feathers coming to rest along her back as her face was pressed close, but not crushed, to warm fur and she gets a heady draw of one of the most wonderful scents in the world; Celestia's.
It was as warm as the mare that made it, light and airy as sunlight on a clear summer morning, full of dew and hope and life. In such an embrace there could be no fear, no panic, all of that burned away.
That comfort only made her even more aware of her arousal and the scent in her nose fans the flames even more, making her need almost painful.

Celestia steps back once more, but keeps her wings wrapped around Twilight, the tips of her feathers stroking down her back, though her tail hairs and the fur underneath that. The action gets a cute mix of little giggles and light moans from her toy.
Carefully spreading out her weight Celestia lifts her right fore-hoof up and runs it along the inside of Twilight's back left thigh. The contact of cold metal against hot flesh gets a small jerk and a light hiss from the unicorn, though her bonds prevented her from going very far.
The princess moves her hoof up slowly, not stopping and going through the sopping wet fur and right to the source of that moisture.

Twilight bucks hard against her bonds when that cold hoof-cap made contact with her burning neither lips, a hiss-moan of pleasurable pain slipping past her gag as she shamelessly ground her body against the direct stimulus.
The glow from the base of her horn now looked like it was trying to rival the light of the sun itself, the purple glow bathing the whole room. Yet the inhibitor ring held, not even having the decency to glow or show any kind of signs of having trouble holding back the massive amount of magical power on display.

Celestia moves her hoof in time with Twilight's body, carefully keeping it away from the 'button' at the top of her folds. After a few more moments she presses her body closer to the smaller mare, pulling her wings tight at the same time, preventing Twilight from moving more than a few scant millimeters.
Angling her head Celestia once more nips an ear, then the other, moving on quickly to nuzzle once more at the base of Twilight's horn. The brightness did not bother her eyes. She was, after all, the Solar Princess. The few lumens added from the contact didn't matter either.

Twilight was shaking so much now all her bonds rattled, her fore-legs pulling all of the slack from the chains holding them aloft and making said metal almost sing from the vibrations of her tremors.
She had lost all conscious control of her body now, all rational thought subsumed by the overwhelming need that permeated her entire being. She couldn't even moan any more, her mouth dry and spent, throat parched and cracking. Nor could she whine or groan, too weak for any more sounds to come from her.
Or so she thought.

The princess kissed and licked her way up the purple horn, each point of contact below the ring caused a strong quiver in her tight grasp. She carefully avoids the ring itself though, going above it instead.
Touches there got no reaction though, giving her student precious few moments to recover.
Once at the tip Celestia pauses for a fraction of a second before swallowing the horn in one motion, her muzzle being just long enough that the tip only barely touched the top of her trachea.
Twilight gives a small mewl as the lips wrap around the base of her horn, body humming and shaking with desire. She arches her back just slightly, as much as she could really, begging in her silent request.

Celestia works her tongue over the base of the horn again, grinning at the small sounds this gets from Twilight. She flicks her tongue over the ring once, an action that disrupts its control over Twilight's magic just long enough to cause the little unicorn to gasp; only to groan as once again magical, and as was her case, sexual release was denied to her.
The princess carefully takes the ring in her teeth, having assured herself of where the catch was located with her tongue. With a gentle bite there is a click and the latch on the inhibitor ring swings open, falling away and out of her mouth as she opens her teeth and lips enough to let it pass, it rolling down Twilight's head to plock on the floor, in the puddle under the purple mare. Celestia draws her hoof up along the wet folds it was pressed against, pushing hard against the purple nub at the top at exactly the same time she removes the ring.

Twilight howls her pleasure around the gag, her whole body going ridged as a flood of juices rush out between her legs, around the gold shod hoof and coating it fully. But not only that her horn flared bright enough in Celestia's mouth that had there been anyone else in the room they could have seen the glow through the white cheeks, the pencortus literally swallowing down the magic without any trouble what-so-ever.
Physical liquid and mystical glow continue strong for a good half minute before slowing, the latter stopping completely first while the former goes back to the plick-plick-plick pace it had been before.

Once things had calmed down Celestia pulls her muzzle free, giving a lewd smack of her lips, running her tongue over them as if she just had savored a glass of fine wine. For the first time of the night her own horn ignites with a golden aura, wrapping around the bit gag and the blindfold, carefully pulling them both off Twilight and setting them aside,
Twilight only had a brief moment to work her jaw before her muzzle was covered by her mentor's, the long royal tongue shoved deep into her mouth.
Not that she minded of course. She could feel and taste her magical aura on that tongue, but that didn't matter and she pressed back with her own tongue eagerly.

The kiss was short, almost painfully so for Twilight who leans forward as Celestia pulls back. The solar diarchic only gives a light smile before raising her soaping hoof and pressing it against Twilight's muzzle.
The purple mare didn't hesitate a moment, her dry tongue darting out and lapping away her own juices from the magically still cold metal. It was a familiar taste; one not at all offensive to her and the moisture was very welcome to her dry mouth.
The hoof cap didn't have much on it though, and from this angle she couldn't reach the soaked ankle. She gives one final lick and pulls back slightly, running her tongue over her lips once as she looks to the ground.

She catches the golden glow of Celestia's aura out of the top of her eyes as it wraps around her fore-hooves and the chains holding them. The magic was warm, comforting and gently massaged her numb limbs while lowering the chains some before the manacles pop open.
The solar magic didn't release though, instead carefully sitting her back onto all fours instead of being up on only her hind legs. The magic also helped with blood flow and prevented any pain for the moment. They would be sore later, as would her whole body, but not right now. This night wasn't done after all.
Even with the princess's magic helping as soon as Twilight's fore-hooves were back on the floor she sagged just a little, almost ready to collapse but she pulls up some inner reserve and remains standing. Her favorite part was about to happen, and would be much more enjoyable while standing than laying on the cold stone floor.

Once Twilight was steady Celestia cuts her magic and stands up herself, turning away and promptly flicking her tail up along her back, showing off her wet inner thighs and winking mare parts.
Not needing any more invitation than that Twilight leans forward and presses her muzzle against those soft lips, driving her tongue into the passage they protected in search of moisture. She was careful of her horn though, angling her face so as not to poke the royal rear.
It didn't take very long at all before Celestia gently pressed against a little more, quietly showering Twilight's face with orgasmic fluid, a substance the smaller mare eagerly drank up, not letting so much as a single drop go to waste. The very idea of that was akin to heresy in her mind.

Once her climax passed Celestia allowed Twilight a few more licks before she pulled away, getting another cute whine from her little submissive. She turns and with another short burst of magic cuts the leather straps holding the manacles on Twilight's rear hooves in place. She, however, still leaves the bar holding the rear legs open in place. Stepping back a pace she draws the young mare along with a light graze of her wings before pointing to the large puddle on the floor.
Of all of their activities, of all of the things they did together, of the things Celestia did to her and of the things she did for and to Celestia this was one of the acts that always made Twilight blush under her fur. No matter how many times she was forced to do it, it never failed to cause her a little embarrassment. And that was precisely the reason she was always told to do it and the reason she obeyed.
Turning away from her lover Twilight bends forward, the bar causing her rear to go up into the air and the rope kept her from lowering her tail, not that she would have anyways. This gave Celestia a very good look at Twilight's assists, a sight she had seen many times before but was always happy to see again.
There was only a small amount of hesitation on Twilight's part before she started to lick up her own juices from the floor as her mistress watched.

Once about half of the standing pool was gone Celestia leans down to lap directly from the source, her long dexterous tongue slipping in deep with one slow motion. This causes Twilight's back legs to lock and her front ones to almost give out on her. She gives a deep moan and a few pants before going back to her clean up task, horn once again starting to glow.
But once again it was only a light teasing and full denial, Celestia only building the fire back up from the embers it had fallen to. She pulls back, once more smacking her lips before lapping them clean, grinning and with barely a side thought pops open the remaining manacles when most of the puddle had been removed.

When the bar hits the floor with a very audible clang Twilight felt her rear hooves give out on her, diving her face into the last remainder of her juices. This happened every. Single. Time.
Every time.
She knew it did, she knew. But she still could never seem to be ready for it when it did.
Getting up onto all four hooves again she turns to Celestia, face burning under her fur, the right side slicked down and reeking of her arousal.

Celestia laughs again and Twilight gives a small smile, looking up to Celestia's face of her own accord for the first time that night. The two of them share another, longer kiss. Then they move to each others sides and head for a shower in the corner of the room to clean up some.

"We fooled around a bit more after that but the main session was over. So that's what I did the last time I was in Canterlot." Twilight finishes her little story and tips back the last of her Apple Family Special Reserve Hard Cider, drunkenly smacking her lips before lowering her mug to the table, magic unaffected by her level of inebriation.
Her five friends were in a circle with her at the table in the library's dining room, staying the night for a sleep over. Four of them were giving her dead pan looks, even Pinkie was at a loss of anything to say for once. Fluttershy was, of course, the only one not staring at Twilight; instead she was hiding her very flushed face behind her pink mane, trying to look as small as she could and trying, but mostly failing, to keep her wings at her side.
For her part Twilight was completely oblivious to their predicament, instead looking at her empty mug and giving a light sigh.

"Well, I'm pooped girl, I think it's time I got some sleep. Don't stay up too late now." She stands from the table and stumbles a little. No one stands to help, still too surprised by what they just heard. Twilight manages to make it to the stairs and heads up to her bedroom, which had been cleaned up and the bed removed so six sleeping bags could be put on the floor in its place.
Once she was gone from the room four sets of eyes look around at each other, blinking after a too long moment. Rainbow Dash finally speaks up, sufficiently summing up all of their thoughts on the matter.

"What. Just. Happened."