Rainbow Dash was almost thankful the train car was empty save for Twilight, but couldn't really be grateful for anything she was enduring. She'd have already died of embarrassment if anypony else could have seen her sorry state. But with her struggling to keep her bladder in check like a little filly, it was already too humiliating for her to bear, even without an audience…

Legs crossed in a vice, the muscular mare kept one hoof shamefully buried between her thighs at all times to maintain pressure on her marehood. It was all she could do to keep the flood from gushing over her seat and cascading to the floor. Trying not to jostle her bulging bladder, she angled her head to gaze out the window and look down the tracks, almost weeping when she caught sight of the station in the distance. It was nothing more than a flimsy building and a few trees in the middle of nowhere, but it had to have a bathroom. All she had to do was hold it a little longer, then the nightmare would be over, and she trusted her friend not to ever speak of it again. Nopony would know how close she came to an accident.

"Just seven more minutes, Rainbow Dash." Twilight encouraged from the seat opposite hers, her expression one of gentle reassurance. Not daring to meet her friend's gaze, Rainbow tried not to whine at the misguided encouragement, now keenly aware of every second ticking by thanks to the introduction of a countdown. The very beating of her heart was like a badgering drum against her bladder, the rhythmic spasms making her legs twitch every time the pain rocked her floodgates. A weaker pony would have been quaking in their own puddle by now, especially with the repetitive pain making it so tempting to let go. Granted, she was still far from in the clear, and a lot could happen in a few minutes…

Ka-THUNK!

A bump on the track jostled her floodgates like an earthquake and tested her theory all at once. Even with the strength of a Wonderbolt, she felt a burst of warmth rush over her underhoof and spread through her folds. Icy dread pitched through her stomach, and with a panicked shift of her legs to regain control she felt a second hot spurt sprinkle between her thighs. Praying Twilight hadn't noticed, she clamped down with her wet hoof harder than ever, pressing so tightly on her marehood it burned. Any amount of pain was worth bearing if it meant she didn't pee herself, especially after all she'd done to hold it these past few hours! Folded legs trembled like leaves in the wind as she grit her teeth.

Chest heaving as she teetered on another leak, Rainbow Dash looked again to the window. Between tears and the fog of her breath it took a terrifying moment for her to locate the building she'd seen in the distance. By a miracle she didn't care to question, the station was now moments away down the track, and an outhouse was clearly visible at its side. She merely needed to fly a few measly feet once they came to their stop and she'd be free.

Twilight jumped to her hooves just as the train started to slow down, fully aware of the severity of the situation and how not a moment could be wasted. Equally cognizant of how easily she could fail at the finish line, Rainbow Dash took a few precious moments to carefully unfurl her wings and alight, the momentum of the car coming to a halt sending her bladder sloshing most painfully and slowing her down considerably. By the time she was airborne there were tears blurring her vision, which was to say nothing of the blush rising across her cheeks. She didn't need anypony to tell her she looked ridiculous flapping along with her hoof buried between her crossed legs. Judging by the draft over her rump, she also had a not insignificant bit of damage from her leaks… A quick turn of her head revealed a few shameful droplets across the chair she was leaving behind.

Ever the faithful friend, Twilight accessed her magic and opened the door to the car the instant they were stopped, bypassing the controls in a desperate bid for the sake of her friend. "I've got the door, hurry across to the-!"

Rainbow didn't let her finish, too far gone to offer gratitude or to care about how cool she looked zipping out of the train with her hooves clamped between her legs. Aiming for the outhouse, she flew faster than she should have at such a short distance, so desperate for relief she didn't care about safety. It was all coming down to the wire. Every beat of her wings sent a burst of pressure down her belly she didn't have the strength to overcome, resulting in a series of spurts she was powerless to stop, save by pressing her tail against her labia and sacrificing her rainbow hair. Warm piss squirting in her wake, she prayed her tail wouldn't be too soaked by the time she pried it back from her marehood…

She was so seduced by the prospect of relief that she failed to notice the sign hanging on the outhouse until she was flaring her wings in a panic and braking to a halt.

Every word hit her like a kick to the bladder.

Out of Order

The sign hung low and dusty and unkempt, giving no hope of a last minute janitor to the rescue.

"Oh come on…" she wheezed in defeat, a hot dribble gushing past her hoof and tickling down her leg to patter on the wood below. Of course, the one outhouse for miles, and it was broken. She wasn't going to make it. Crushing humiliation almost knocked her to the ground, her blush spreading from her muzzle to the tips of her ears in a crimson rush of heat. It was all for nothing; she was at her limit, barely able to fly, and there wasn't a bathroom in sight…

Twilight gasped in horrified sympathy for her friend as she hovered before the broken bathroom, but wasted no time before looking for a solution, refusing to accept defeat even as Dash tinkled onto the platform with increasing force and volume. Spinning on the spot, she searched every corner of the unoccupied station for a last minute substitute to an outhouse.

Sweat dripping over her brow as piss dribbled down her thighs, Rainbow Dash shook with a sob, helpless to her impending accident. Not even the grip of her hoof was enough to keep it all in. A thin tinkle was coming out without interruption, and by the time she realized she couldn't stop she had already let out too much, the fur about her folds growing soaked with her unstoppable leaks… Tears burned the corners of her eyes as she squeezed them tightly shut. "I can't… I-I'm gonna…"

Reasoning that any waterproof container was better than none, Twilight pointed to the only one in sight, shouting to get her friend's attention. At this point, the best they could hope for was to salvage the situation. "Dash, use the trash can!"

Snapping her eyes open and twisting her head around, the leaking Wonderbolt felt her stomach lurch in humiliation at the sight before her; Twilight pointing frantically, the lone dusty bin, and her out of time... It was bad enough she was this desperate to begin with, but was she truly so out of options she'd plant herself on a trashcan?

The most painful spasm yet from her bladder answered the question for her; yes, she would, and she'd do so posthaste!

Trying not to cry in front of her friend, Rainbow furrowed her brows and turned her whole body, struggling not to keen at the pain of every wingbeat. Hooves dripping and legs criss crossed with piss, the mare lurched forward and didn't let another spurt stop her progress, the trashcan now beckoning her with the consolation prize of relief from her nightmare. By now the agony was ever present and overwhelming, her bladder spasming and her marehood throbbing, and the last few moments of enduring her torment stretched out to mirror eternity. It was almost impossible to think, let alone to fly across the tiny platform that stretched on forever, with her body fixating on nothing but obtaining relief. Sweet Celestia, she was like an overfilled water balloon… It didn't seem much of a stretch to say she was going to burst and flood the train station. Heat filled every inch of her as she closed in on her target and the long awaited release finally became a reality.

Barely able to think, the mare relied on instinct to help her move into position, her hooves leaving her crotch to grab hold of the can. Exposure to the cool air immediately let a thin dribble of piss escape without obstacle, but she let it happen, setting her jaw as tiny streamlets danced down her thighs and over her legs. Prying away her tail also encouraged her strengthening release, the soaked rainbow hairs moving aside to allow a constant series of spurts to rain on the wood in her wake. It couldn't have been more obvious that she was about to burst.

Taking deep breaths, the mare reached out with a single hoof and secured it atop the trash can, preparing to seal her rump over the admittedly perfectly sized hole-

Then, it happened, quite without warning and well before she was in position. Her body hit its limit, just as she raised her leg up to mount her impromptu toilet, and with Twilight at the perfect vantage point to catch everything.

She was unprepared when the call of nature overpowered her defenses in a single motion, and had only a rush of heat through her bladder to warn her before her floodgates crashed down in a single stroke. Endorphins rushed through her veins as wet heat flooded her mound, her pupils contracting to mere pinpricks. Reflexively, her tail flipped completely up and out of the way, making room for her surging stream just as it burst through. Hot piss cascaded to the ground without obstacle, and her legs only spread to grant it passage, the flow hissing loudly and proudly before pattering against the dusty wood below. Crying out in humiliation, Rainbow Dash nearly dropped out of the sky as she battled herself for control, wings flapping desperately out of sync as she clung to the rim of the can for stability. The turbulent flight merely sent her stream wobbling as it rained into the growing puddle below, the surging flood coming out in an occasional spray as her strong muscles clamped helplessly to try and stop the flow.

Just out of range, Twilight startled at the dramatic burst of piss, her eyes going wide as the Pegasus began raining down on the platform. She'd never seen a pony have an accident, and never would have anticipated it happening to a mare like Rainbow Dash, but here they were. Unable to stop peeing, the always tough Rainbow Dash cried out in humiliation, tears streaming down her cheeks as her face lit up with crimson shame. She was having an accident, like a little foal! The wood was submerged by a lake of urine that streamed down through the slats just a tad slower than she added to it, allowing the edges to expand out as the puddle bubbled beneath her shower.

Rainbow sobbed as she continued to humiliate herself, unable to stop when there was still so much that needed to come out. Worse than the fact she was peeing herself, it felt incredible, even with how she squirmed in resistance sending a massive amount of her stream surging down her legs… Fresh tears rushed down her cheeks as she felt the warm urine soaking into her fur, but there was no stopping her jaw from slacking as the bliss of relief started to tingle in her marehood. Humiliation didn't prevent this from feeling like heaven.

Getting a very personal show, the Princess of Friendship found herself enraptured, her capacity for planning under pressure working only on autopilot. Summoning the gentlest of her spells, she grabbed Rainbow Dash in a levitational hold, lifting the peeing pony as she continued to relieve herself. Something within her pulsed most delightfully when she took control of the situation. Though the rainbow haired mare gasped and snapped her eyes open when she was lifted, she didn't protest when she quickly deduced what was happening.

Fresh mortification bloomed in her gut as she was maneuvered over the trash can like a helpless doll, her stream still surging and splashing over the rim of the can before Twilight managed to get her lined up properly. As gently as one would handle a statue of glass, the Princess set her friend down atop the can, unconsciously keeping a hold on her even as she stopped supporting her weight. Rainbow Dash closed her eyes as she was settled over the hole, her release speeding up reflexively now that there was a container to catch the mess. Sighing shakily, she stopped trying to hold it in and took advantage of the modicum of privacy the can offered. Dripping from the haunches back, she pushed down on her shrinking bladder as she entered the latter half of her release, whimpering at the realization she'd gotten more on the ground than in a container.

Regaining some of her composure, Twilight made a point to look away and give Rainbow what privacy she could. Granted, averting her eyes didn't stop her from hearing the ongoing release, or feeling all the things it triggered inside of her… Though the sound was muffled by the bin, the Rainbow Dash was still pissing an absolute waterfall into the empty trashcan, and the hiss of her release bordered on impressive as it cascaded down into the growing pool at the bottom. Her friend had really held it in for her…

"Ahhh…"

Rainbow let out a tiny sigh as she savored a bit of her relief. The bulge of her bladder was now almost flat on her front, and the pressure she'd been suffering under was finally fading away. Though she could have probably stopped her stream with only a third of her burden remaining, she decided to finish, clenching down to speed up her lagging stream. Securing another bathroom would have been far too much trouble.

They sat in silence, save for the weakening waterfall echoing through the bin, which told them both Rainbow was winding up. Her stream fluctuated and lagged even as she pushed down, thinning further as the ocean of piss was reduced to nothing more than a tinkle. Closing her eyes, the athletic mare listened as the last drops fell into the puddle below. A lingering sob made her sniffle.

"I'm… I'm all done." she croaked, voice even raspier after all she'd endured. In the middle of a very impressive amount of piss, she wasn't sure she'd ever felt smaller. Recognizing her friend's plight moved her to action, but Twilight couldn't stop herself from noting every little detail along the way.

"It's okay…" she soothed, gathering every trace of wetness she could find and teleporting it into the bin. Though the hot sun would dry up everything in less than an hour, she figured they would be better off keeping things out of sight. At least they hadn't been interrupted, and the entire area was still free of witnesses. When the platform was as dry as they'd found it, she tried to approach her friend, ignoring how her heart hammered at the memories so fresh in her mind.

"N-no it's not…" Rainbow sniffled, eyes shut as she remained parked over the can. Soaked from the haunches back in her own piss, the mare felt like less of a Wonderbolt than ever before. Trying not to cry fresh tears, she hid her eyes behind the dryer of her two hooves. "I had an accident."

Unable to stand seeing her friend so upset, the Princess of Friendship rushed in, standing on her hind legs and laying her front against the bin.

"You wouldn't have if the outhouse had been working!" she pointed out, plucking the mare off the bin. Her normal shade of blue was notably darker where she'd soiled herself, which was unfortunately most of her lower body, with the worst of it being the sopping fur around her mound. Eyes lingering on the soft folds, she carefully stripped the wetness away and transported it into the bin. Rainbow didn't protest the instantaneous drying. Biting her lip in thought, Twilight carefully set down her uncharacteristically quiet friend before offering another reassurance. "Or if… you hadn't come here to accompany me-"

"You didn't make me come." Rainbow retorted quickly, standing on quaking legs to face the mare that had done so much for her. Still unable to look her in the eye, she mumbled an additional reply as she shifted the weight in her back hooves, not wanting to get distracted by how much better she felt. "It's not your fault…"

"Then it's not yours, either." Twilight assured pointedly, refusing to accept any argument to the contrary. Rainbow Dash didn't want to let on how grateful she truly was, lest she cry again, so she merely nodded. Somehow, someday, she'd repay her friend for this kindness.

She just didn't have the smallest clue as to how.

Author's Note

I love writing to match illustrations, and this piece https://derpibooru.org/images/1812250?q=artist%3Aithinkitsdivine just gave me all the inspiration I needed to get this piece done! I'll probably write out another picture when the time and inspiration are available.

This one will hopefully get a sequel too, one day!