Breezing through the sky on this fine, summer afternoon in Ponyville is none other than Derpy Hooves. The grey pegasus had taken to flying like a child takes to ice cream, having learned at a younger age than most pegasi. However, even to this day, the currently beaming mare often accidentally shows off her rather clumsy side. The breeze gently flowing through her wings as she makes her way toward one of her favorite stops in Ponyville brings a great smile to the cross-eyed mare’s face.

Looking down at the Everfree Forest below, Derpy flies carefully around it before landing right on the bridge leading from the edge of Ponyville to Fluttershy’s cottage. As her wings fold gently at her sides, she smiles and eyes her hefty mailbag before looking straight ahead for any sign of the mail’s recipient.

Just a few yards away, the pleasant and quiet caretaker is tossing out birdseed in an effort to feed her array of chickens and roosters gathered outside their coop. Upon seeing her shy pegasus friend, Derpy trots up behind her and calls her attention in her naturally cheerful voice.

“Hi Fluttershy!”

The loud voice coming from behind her causes Fluttershy to nearly jump out of her skin as she leaps into the air and accidentally spills the bird seed in her hooves all over the soft grass. The chickens swarm around it, pecking as much as they can while the pink-maned pegasus now hovering in mid-air tries to regain her balance. Finding Derpy still on the ground nearby seems to calm her nerves, knowing such an innocent pony could never harm her.

“Oh, hello Derpy! How are you today?”

Her soft voice responds as she glides back down to the ground and lands on the secure footing below. Derpy’s cross-eyed gaze hides itself for a brief moment as she closes her eyes in joy, proud to bring another pony her mail as she announces her purpose for arriving.

“I brought you a letter! It’s my first week on the job as a mailmare, and I’m super good at it!”

“That’s great, Derpy! I’m happy for you!”

Fluttershy’s gentle smile crosses her face as she watches the more than eager mailmare clumsily reach back into her mailbag to fetch the aforementioned letter. After only a second or two of rustling around the various papers and packages inside, Derpy makes a satisfied squeal of joy and grips the piece of mail between her teeth before whipping her neck around.

Her grip is apparently not enough to hold the flimsy paper, as the letter flies past Fluttershy and into a nearby bush as Derpy happily chimes up with her eyes closed.

“Here it is!... Huh?”

Derpy opens her eyes to find the letter previously between her teeth now completely gone, not knowing where it had gone and only finding a slightly confused Fluttershy in front of her. In truth, the mare had narrowly avoided a paper cut across her cheek with how fast that letter had flown right past her, but decided not to say anything, instead looking back at the bush that the letter was now stuck in.

Derpy pouts, her eyes still crossed as she flares out her wings in mild annoyance.

“Aww, did I drop it over there? I’m sorry, Fluttershy.”

The gray pegasus mare trots merrily over to the bush and ends up looking around for a few seconds. Rather unceremoniously, she drops her head into the bush, surprising Fluttershy with her rather direct approach before calling out as if trying to find a lost child.

“Hello? Little letter! Are you in here?”

Fluttershy’s gaze focuses on Derpy looking inside the bush, her eyes naturally attracted to the figure she awaits news from before she finds something far more attractive in plain sight ahead of her. Derpy’s impressive rear end is all there is to see now, the bubbles on her cutie mark making the perfect target for a gaze that has suddenly turned far more intrigued and attentive.

Those flanks and wide hips look as if they have been chiseled by the most skilled sculptor in all of Equestria. That shapely behind is such a perfect sight, she can’t think of anything else to see at the moment, her nearby chickens becoming as lost as the rest of the outside world. Yet, all the while, Fluttershy tries to think, to wonder why she wishes to get closer to another mare’s “plot.”

Words cannot describe the rush of heat and desire flooding her body as she stares forward, taking a light step toward the mailmare out of sheer necessity. Her eyes narrow and her face flushes beet red as her dazed expression becomes quite apparent to the nearby animals. The chickens are merely too occupied with filling their bellies to question their caretaker’s strange behavior.

The shy pegasus finally arrives directly behind the mare perusing the bush near her home for a mere letter of all things. She’s in such a vulnerable position, but that glorious rump of hers seems to beg for attention from anypony who is fortunate enough to lay eyes on it. Fluttershy can’t seem to form coherent thoughts as bits and pieces of these strange desires fill her head.

(“Look... Closer... Touch... Bubbles...”)

Her hooves seem to have a mind of their own as her foreleg reaches forward and, as gently as ever, Fluttershy’s hoof presses into the incredibly soft, plush rump in front of her, eliciting a slight squeal from the mare in front of her.

“Aha! Here it is!”

Derpy pulls her head out from the bush and whips around to present the letter to Fluttershy, her expression showing mere blissful ignorance to Fluttershy’s attraction to her remarkable behind. In her mane lies a few twigs and leaves, showing just how disheveled she became by digging through a bush, but she doesn't seem too bothered by the natural accessories. Staring forward at the mare’s proud grin, however, Fluttershy’s dazed expression seems to fade, leaving her confused and unaware of what had just transpired.

She stands closer than she did when she recalls, but seems to shake it off before grabbing the letter between her teeth and mumbling.

“Uhm... Derpy?”

“Yes?”

Derpy’s shimmering golden eyes reflect her innocence, her tongue sticking out the side of her mouth in a naive smile. Fluttershy considers the mare in front of her to be almost childlike, akin to her friend Pinkie Pie, but she can’t quite put her hoof on what had her so enraptured only a few moments ago. Instead of trying to figure it out, she dismisses the matter with a nervous smile of her own before answering.

“N- Nothing. Thanks for the letter, Derpy.”

“Oh! You’re welcome! I’ll see you later, Fluttershy!”

Derpy’s wings flap a few times before she jumps off the ground and ascends into the clear sky above Fluttershy’s cottage, heading towards Cloudsdale to continue on her next set of deliveries. Fluttershy merely waves a hoof in farewell as an unsure grimace washes over her. Taking a moment to look down at the chickens gathered nearby, the pink maned pegasus can’t help but think to herself.

“What just happened?”

In the rather large cloud city hanging in the sky, one particularly lazy stallion takes a few steps outside his comfy home with a look of sheer anticipation on his face. His dark coat and contrasting cyan mane styled into a mohawk do little to downplay the excited grin he wears. Trotting a few feet away to his mailbox, it’s clear that the pegasus known as Thunderlane is more eager for his mail than other ponies. Considering that most ponies would wait until later in the day to check their mail, the package he is awaiting must surely be important.

“Come on, PlayPony magazine...”

The stallion mutters under his breath as he reaches for the lid and closes his eyes in suspense. Gritting his teeth, he opens the lid with his hoof and peers inside with a wide smile on his face, only to find nothing inside. Immediately slumping at this result, Thunderlane shuts the lid to his mailbox and lies on the comfy cloud supporting the weight above it, feeling impatient after having waited so long.

“Damn it. This thing is taking forever.”

“Thunderlane! Special delivery!”

Upon hearing his name being called, Thunderlane’s ears perk up before his gaze seeks the source of the lilting voice. The one and only Derpy Hooves flies towards him slowly, taking her time to ensure she is being careful with her mail.

A half-smile forms on his face as the mare approaches and touches down in front of him. Feeling obligated to reply, Thunderlane remarks in a somewhat defeated tone.

“Hey there, Derpy. What’s with the bag?”

The stallion refers to Derpy Hooves’ mailbag full of letters and small packages made for easier delivery. The mailmare still puts on a confused face and looks to her side at the mailbag hanging over her by a loose strap. Realizing what he’s talking about, she turns back to him and answers while wearing a gleeful smile.

“That’s my mailbag! I’m a full-fledged mailmare now!”

Lifting her hoof and striking a pose, Derpy sticks out her tongue and winks at Thunderlane, her playfulness managing to exaggerate the joy she has at having what other ponies would consider a mundane and dull job. Thunderlane still chuckles however, going along with her even though, inside, he is genuinely surprised a mare like her has gotten a job already. He’s still at home living with his parents and his little brother after all.

As Thunderlane lets out a dismissive cough to ignore that thought, Derpy quickly adds on to her previous statement with a much more interesting piece of news.

“Aaaaaaaand I have a package for you!”

Thunderlane quickly picks himself up off the surface of the cloud and practically jumps into the air as his wings flare out in giddy expectation. Looking at Derpy with a greedy shade of dark gold irises, the stallion impatiently pesters her for the promised delivery.

“Great! Aww, Derpy, I knew I could count on you! So where is it? Is it in the bag?”

“Oooh! I think so! Let me check!”

Derpy matches his excitement with a happy smile of her own before gently resting the mailbag onto the ground beside her and turning to lean down and search through it. All the while, she makes happy humming sounds as she digs through the sack with her hooves to find what she’s looking for. Behind her, Thunderlane stares at rapt attention, his eyes drawn to the bag in front of him before something rather large obscures his view and causes him to lose focus.

His eyes seem to narrow as the plump globes in front of him demand attention from the stallion behind them. Thunderlane’s greedy eyes shift toward the luscious behind of the mailmare, bent over with her flanks raised high and her tail swishing playfully. A blush forms on his face as he finds himself unable to look away, embarrassed of the situation as he may be.

This is no ordinary plot. To Thunderlane, it might as well be the sexiest plot he has ever seen in his life. That amazingly round shape and pillowy soft flanks are enough to get his blood surging to his member to draw it out of its sheath. Of course, with only Derpy’s seductive rear end on his mind, it makes perfect sense that Thunderlane should get hard and want to desire her.

Gulping nervously, Thunderlane manages to question himself in a light whisper as his eyes follow that shaking plot from side to side.

“What the hell is wrong with me? She’s just a cute mare, right?... Right?”

(“Sweet Celestia she’s hot... I don’t know what I’m thinking but... I need that body, I have to fuck those sexy flanks!”)

As if following the sudden desire burning within him, Thunderlane moves forward and places both his hooves on the mare’s plush bottom, briefly squishing them together to see just how amazing they are to feel as well. Derpy doesn’t seem to notice this, however, only letting out a disappointed groan as she stops peering through the bag and turns to look back at Thunderlane with an apologetic sadness shining in her eyes.

“Aww, I can’t find your package in here! I must have dropped it on the way... Darn it, that’s the third time today!”

Derpy whines in a rather cute manner, her scrunched face still visible in the corner of Thunderlane’s vision. However, no matter how cute the mare in front of him is, he has his sights set on something he considers far sexier. With his hooves pressing into Derpy’s plot, Thunderlane leans forward until the tip of his now incredibly stiff stallionhood bobs just inches away from her marehood. In a dazed voice, the mesmerized stallion utters a cheesy remark in response to Derpy’s worries.

“It’s okay, Derpy. I know just how you can make it up to me. See, I have my own package that needs to be delivered~”

“... I don’t get it.”

Derpy replies, a confused expression washing over her as Thunderlane tries (and fails) to imply naughtiness to the relatively naive mare. Thunderlane seems to ignore her, however, now getting close to mounting her as his hot and throbbing member presses against her marehood and begins to smear his precum along it. Thunderlane can’t help but shudder under the pleasure coursing through him as her flanks seem so eager to welcome him inside her.

“Nnh, Derpy... Just let me ride those flanks of yours...”

“Ride? Oh, I love rides!”

As if suddenly remembering the childlike wonder of having her first piggyback ride, Derpy backs up and rears up so her forelegs dangle in the air happily, exclaiming aloud.

“Giddy-up!”

The movement throws Thunderlane off balance and he falls backward onto the soft cloud they stand on before Derpy soon follows suit, her heavy body landing atop him with a thud. Before Thunderlane can tell her to get off and stop from crushing his waist, he feels a warm, soft sensation wrap around his hardened cock. Opening his eyes, he finds both sides of his stallionhood clenched by the mailmare’s firm buttocks.

An overwhelming sense of comfort and security from being lodged between Derpy’s flanks overtakes Thunderlane and leaves him practically drooling as Derpy herself feels something slightly off about this position she has found herself in.

“Hmm? Something’s poking me... Oh well! Wee!”

Derpy happily proclaims as she begins to quickly bounce up and down on Thunderlane’s waist, forcing his member to slide between her flanks in such a playful yet naughty fashion. The stallion suffering such pleasurable torture merely stares down at her flanks and thrusts his hips upward to aid in her bouncing, loving the feeling of this mare’s amazing plot.

By now, he has completely forgotten about his package, surrendering completely and totally to Derpy’s rear end. There’s just something about it that makes him want to do such naughty things to her, regardless of the fact that he has never found himself attracted to her . How has he not seen it ? Derpy’s ass is perfect, and everyone should know this pleasure.

Thunderlane grits his teeth at the amount of pleasure in his throbbing stallionhood as its veins become more apparent. In an effort to slow her down to savor the motion, the stallion grabs at her flanks with his hooves and forcefully rubs her bottom up and down on his member to elicit the most possible pleasure out of him. Derpy doesn’t notice this, instead opting to bounce on top of him even harder than before, ruining his slow motion with one of quick vertical thrusts right into the soft cheeks hugging his member gently.

“Wee! This is fun!”

Derpy seems to have forgotten all about her service as well, now “riding” Thunderlane without a care in the world. She’s having plenty of fun, even as the undeniably lewd nature of the situation is completely lost on her. Right now, she’s fucking Thunderlane’s stallionhood with her flanks, and the smile on his face is just as wide as the one on hers.

Unable to hold back any longer, Thunderlane groans out in warning even as more thoughts of the grey mare’s flanks consume him.

(“The bubble butt... gotta cum all over it... bubbles...”)

Without so much as a single word escaping his lips, Thunderlane rocks his hips upward as spurt after spurt of thick stallion semen shoots up and begins to coat Derpy’s back and rump. All over her grey fur is now an off-white sheen, soaking into her and causing her to slow to a stop as she feels the liquid leave quite a mess on her.

"Aww, is the ride over?"

Even as her tail swishes lightly behind her and Thunderlane continues to pump into her flanks absentmindedly, Derpy doesn't seem to know what’s going on, now looking back at Thunderlane’s incredibly pleased face. With no idea of what to do next, Derpy questions aloud and holds a hoof to her mouth as she thinks deep, pondering thoughts.

“What’s all that sticky stuff, Thunderlane?... Thunderlane?”

With his member still twitching and throbbing slightly, Thunderlane is seen with his head tilted back and an impossibly wide grin on his face, as if he has died and gone to heaven. With his eyes closed, he can no longer see her flanks, and, as such, his blank mind seems to return to coherent thought... if only for a few brief seconds.

“D- Derpy... flanks... goooooood...”

Speaking single words during pauses and heavy panting, Thunderlane seems to pass out where he is, right outside his home with some evidence of what has transpired now pooling at his groin. Derpy then stands up and turns around to look at Thunderlane, watching him for any signs of movement and prodding him with her hoof delicately.

“Thunderlane? Huh, I guess he must really like rides!”

With that said, Derpy picks up her mailbag and slings it over her back, accidentally grazing the bottom of the bag in seed, all while blissfully ignorant of what had truly happened. Looking off to the rest of Cloudsdale, she remembers that she still has more deliveries to make and gasps aloud in surprise.

“Oh gosh, I almost forgot I still have to deliver a package to Lucky, too! I hope this one’s in here, next time. I can’t let a little fun distract me at work!”

Derpy merely smiles and flaps her wings to ascend into the bright blue sky once more, the fresh droplets of cum quickly leaving stains on an otherwise flawless behind.

Author's Note

Quite possibly one of the silliest ideas I've ever had, which is exactly WHY I wanted to write it. Combining my love for both the incorruptible innocent with unrelenting perversion is something I always wanted to try, and Derpy has a bubble butt. All arguments are invalid.

Got more chapters to go. Hope you like!