"So, how do you like it?"

The question came for the fashion designer waiting patiently for a verdict on her latest outfit. Rarity bit her lip awaiting that answer, one which could potentially be a career breaker. It seemed silly to get so worked up over one outfit, normally she'd be able to get over it quickly and straight back into designing a new one, with renewed determination to get it right. When your client is none other than Princess Luna, standing in her personal chambers with her as she was making her mind up, then that decision of whether its a good outfit or not holds a lot more weight.

Luckily for her, the princess was smiling. "Oh we-I mean, I, love it!" Luna corrected herself, checking herself in the mirror. She was still trying to break out of the habit of using the royal we and old canterlot dialect, but it was proving difficult.

Rarity simply beamed at the praise, but inside a wave of relief hit her that took the tension out of her. She had lost sleep over the fact that Princess Luna had commissioned an outfit from her, agonising over every minute detail in creating the outfit. True, she praised herself for her fashion sense and skills at seeing that fashion take shape, but there was still that nagging suspicion in her mind whenever she presented an outfit to a customer that they'd turn around and say they didn't like it. Hearing praise straight from the pony's mouth was a blessing.

"If I may ask, how did you reach the decision for this particular ensemble?" The princess inquired, turning away from the mirror. “If I recall, its a little outside your usual range of dresses.”

“Well, you asked for practicality and beauty, and you specifically said no dress, so I thought that you'd need an unrestrictive outfit, one that could exaggerate your fine figure.” Replied Rarity, noticing that she was perhaps a bit too quick and enthusiastic with that comment on her figure.

“It does feel very nice, and makes a good change. I have far too many dresses, some I never get round to wearing, thought I might need something different.” She had turned back to the mirror, examining the back of her, pulling poses in it to get a feel for the outfit. “Continue.”

The little unicorn gulped. Truth be told, she may have outdone herself. Luna looked simply gorgeous. The princess had pinned her hair up into a sporty ponytail at the designers suggestion with a black vest covering her top half. On her fore-hooves were black wristbands with a white crescent moon emblazoned onto each one, with her back-hooves wearing plain black running horse shoes. A bit simple for Rarity's taste, but this was an outfit made for running, and if Twilights opinion is anything to go by, sometimes simple works.

But it all paled in comparison to the lower half of the body. Plain white leggings that hugged to Luna’s figure like a second coat, emphasising it and leaving nothing to the imagination. More than that, before Luna put on the ensemble, Rarity never noticed how good her derrière looked. She found herself staring at it, mesmerized by it, and the poses made by the princess were not helping her need to pull away her gaze, but eventually she managed this impossible task.

“Err... ahem!” Rarity coughed, mustering up the courage to be honest with the princess, speaking quickly. “The colour I thought would be a nice change to your comfort zone, white working as a nice contrast to your coat, and the leggings are of a material that hugs to ones figure and complement your juicy, well toned derrière if I do say so-”

Immediately, Rarity clapped her hoof to her mouth to stop herself. Did she just describe Princess Luna's buttocks as juicy?!

Luna giggled at this. “It is isn't it?” She said, giving her tush a wiggle “I've noticed you've been staring at it for some time, even before I got dressed. You adore my posterior, no?”

The white mares bottom lip quivered at this question. But she finally caved and decided honesty was the best policy. “Yes...” she said, barely over a whisper “I-its... simply stunning...”

“Humph!” Luna snorted 'We should hope so! We pride ourselves in our buttocks more than any part of our body!” Almost immediately after saying this, Luna laughed out loud at her over the top delivery. “Tell you what, what, how would you like an alternative form of payment, on top of what I've already given you?”

“Rarity shook her head furiously. “Oh no, I couldn't ask that, not as payment!”

“Then as a friend offering a service to you.” Luna retorted, giving her flank a smack. “Free reign to do whatever you please to it!”

Rarity nearly fell over at the remark, her legs suddenly losing strength “I... I-I... what?!”

“Did we stutter?!” Luna bellowed in her infamous royal canterlot voice, sending the curtains blowing in the wind of her voice. She then poked her tongue out to reassure the quivering mare she wasn't actually angry. “I mean it, I've been through meeting after meeting today, I need something to spice up my nights. Of course if you don't want to thats fine, but my offer stands. Do what you like to my royal tush!”

Rarity was torn on this. One the one hoof it was indecent to even consider doing anything to the princess. What if she backed out? What if what Rarity had in mind was too lewd or strange? On the other hoof, Princess Luna had just presented her glorious rump to her and said to do whatever to it. This was a once in a lifetime opportunity right in front of her, but still didn't want to do anything to hurt the princess or anything that would ruin the outfit or its contents, so nothing too painful.

Well, maybe just a quick whiff wouldn't hurt, she thought to herself. Rarity approached slowly, her eyes never leaving the prize in front of her. “Are you...positive you're okay with this?” the unicorn asked.

Luna poked her tongue out in that playful manner again. “Go for it.”

Rarity leaned in close, her heart racing. Was this happening? She was about to take in the scent of a ruler of equestria, Princess Luna’s bottom. She felt lightheaded with excitement, and as she inhaled through her nose to take in that smell, she decided no.

One quick whiff isn't enough.

Rarity brushed her purple mane out of her eyes before pressing her muzzle straight into that glorious, white canyon in front of her, taking a long breath through her nose and exhaling a moan of pleasure into that rump.

Luna wiggled her hips in approval, enjoying the comfort of the little unicorn pressed into her hindquarters. Deep down she'd always been curious about doing this, but knew none of the royal guard would indulge this strange fantasy of hers. With Rarity here though, she saw her opportunity and took it.

Pulling out of Luna’s rear, she then kissed the left check, then the right one, and finally right in the middle before resuming her sniffing, never getting enough of that royal smell.

“Enjoying yourself back there?” Luna asked, craning her neck to look at the unicorn, seeing only a purple mane and the top half of her head, eyes closed and pressing into that well toned end, seemingly oblivious to the question, unless moaning into the royal flank counted as an answer.

Its only when Luna coughed that Rarity was brought back to reality, eyes shifting left and right searching for a conceivable reason for her to cough. “I'm sorry, did you say something darling?” she asked, grinning sheepishly.

“I said, are you enjoying yourself?” Luna repeated.

“Oh very much so. Though... if I may make another request...” The white mare nodded her head towards the bed.

In response, Luna pointed to the bed, then to her behind questioningly, to which Rarity nodded furiously. “Then make yourself comfortable.

There was a streak of white as Rarity rushed to the bed, already resting her head on a pillow. Luna giggled once again at her enthusiasm, then climbed onto it and turned round, presenting her hindquarters to the unicorn.

The white object above Rarity came down slow. Very slow, coming closer and closer to her face. It then stopped at her nose, brushing it and teasing, hanging there so very close. Rarity actually whined at the sensation, needing more of it, taking in as much of the scent as she could through her nostrils.

“Kiss it.” Luna ordered, bringing it higher away from the pony’s nose.

Rarity was more than happy to oblige, kissing that well toned white heaven above her, over and over again, each peck sending a shiver of pleasure down her spine. This continued for a full minute, Rarity planting kisses all over Luna's booty.

“That'll do.” Luna eventually said, lifting it higher. “Now relax. We shall do the rest.”

And with that, Luna lowered her large rump encompassing Rarity's entire face and got to work. She started by swaying her hips from side to side, the unicorns snout following where ever it went, then lightly bouncing on her face. Luna was having the time of her life, moaning in pleasure as she worked her posterior on the little pony's face, she couldn't even imagine how the mare below her must be feeling.

Rarity could scream she was in so much pleasure. The weight of Luna over her face, the material of the leggings, a wise choice she mentally noted, the way she worked it, it all felt... right. Like she was meant to be under the princess. She squealed and groaned into Luna's legging as the princess worked her magic, relishing every sensation. She wanted it to last forever.

As Luna rocked her hips backwards and forwards grinding her rear on the mares face, she felt the need to bring this to a close. After a few more grinds, lifting off of the unicorn, she turned her head to look down on her. “Hold thy breath.” She said, a devilish grin on her face.

Rarity barely had time to react before Luna put her full weight on her, blocking her vision and hearing. She tried to turn her head, but couldn't. Luna was pressing down that hard. She resisted moaning again, enjoying the restriction but determined to put up a good fight. Her breath was fading, adding new layers to her joy, her senses were clouded by the smell of new fabric and of the princess herself. There was literally nothing else in her world now, except the smell that she desperately wanted to inhale and the royal rump entombing her.

Eventually however her breath gave out as she screamed into Luna’s bottom, writhing and kicking, desperate for air. The princess obliged, but only slightly, with her derrière just high enough to get air, but still resting on Rarity's face, leaving her to breath in her scent.

“So, how was it?” Asked Luna, smiling down on the breathless mare.

“That...” Rarity gasped “Was...oh my... it was... magic...”

“I hope you like it as much as we- sorry, I did.” said Luna, getting off the bed.

Rarity still wouldn't move, still getting over the princess of the moon sitting on her face. “Can we do that again someday?” Rarity pleaded “Oh that was quite possibly the highlight of this year, no, my entire life! Can we? Please?” She finally found the strength to peel herself off the bed, shooting the princess puppy eyes.

“Tell you what, when you come with a new outfit, we can try it out again.” Luna said, giving a wink to the mare.

Rarity then made very strange noises that built up in volume before erupting into a squeal of delight. “Oh thank you! Thank you thank you thank you!” Rarity squealed, kissing Luna's fore-hooves in respect over and over again, then, feeling extra mischievous and giddy, she planted a big fat kiss right on her flank before giggling like a little filly out the door in a blur of white.

The unicorn sprinted out of the castle towards the shops.No time for rest, no time for anything. Rarity's mind raced with possibilities of new outfits to see Luna in, new materials to be underneath and breath in. She was on the biggest high of her life and no pony was going to stop her!

Chaps, she eventually decided on. Butt-less chaps.

Author's Note

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