The Preparation
Rainbow Dash was tingling with excitement, the long day of training was finally over.
"Alright Wonderbolts, time to hit the showers." A loud, gravelly voice called out.
Wings sore from the relentless day's training, the Wonderbolts glided down to the doors of their headquarters.
Rainbow Dash quickly packed her saddlebags and slung them over her back, still covered by her uniform.
"Hey, Dash!" Turning around, Rainbow Dash saw Fleetfoot trotting over to her. She had already stripped out of her suit and was balancing a thick, white, fluffy towel on her back. "You're going home now, aren't you going to have a shower?"
"Naa, going to have to have one at home, no offence to the Wonderbolts showers, but mine is way better. Besides, I don't want to see you and Blaze try and feel each other up."
"Jealous?" Fleetfoot said with a smirk.
"Ha, you wish. It just makes trying to clean my wings a pain."
"That just tells me you want in."
"Knock it off Fleetfoot."
"Okay Dash." She walked over to the doorway, "But remember, it'll be just me and Blaze, hot water pouring over our coats, soap making us nice and slippery, just right for..." Seeing the look on the blue pegasus' face, she trailed off. "Anyway, see you around Dash." She trotted out towards the showers.
As Rainbow Dash finished off the last of her packing, throwing her shampoo in her bag, she felt a sharp cramp in her belly.
Unknown to the rest of the Wonderbolts, Rainbow Dash had not been to the toilet for three days, and now it was starting to take its toll on her. Another cramp, she groaned as a small raspy fart escaped her strained anus.
What if I just let out a little? She thought to herself, I mean, nopony's going to know, and besides, it'll feel good on the flight home.
After debating the issue for a few moments she made up her mind. Rainbow Dash rose her tail slightly, spreading her hind legs just a few more centimetres apart as she prepared herself.
She looked left and she looked right, checking if anypony could see her in the deserted changing room. Coast clear, she relaxed her taut anus.
Instantly she felt the load inside her move. The head of a thick log of manure poked out of her thick ponut, hidden by the blue of her suit. Not wanting to make too much of a mess while still in dangerous territory, the blue anus clenched, cutting through the soft scat, leaving a golf ball sized lump of pony poop nestled between her firm ass cheeks.
The small squishy ball was pressed firmly against her fur, the skin-tight material of the Wonderbolt uniform making sure that the warmth of fresh shit never left her ponut.
This blessing, however, was a double-edged sword, the enjoyable tightness of the suit also meant that anypony who looked at Rainbow's cute little rump would also quite clearly see the small lump beneath, and it wouldn't take a genius to figure out what that lump was.
Lucky for Rainbow then that her tail, if used correctly, would hide the dirty deed from anypony who looked at her rear.
As Rainbow Dash lowered her tail to its natural position, she heard a loud raspy voice from behind her.
"Hey Rainbow Dash!"
A thousand and one thoughts flooded Rainbow Dash's mind. Please say she didn't notice me. Oh crap, I'm gonna be kicked out of the Wonderbolts... They flashed through her mind like the lightning from a storm cloud.
But another part of her mind wondered if it would be such a bad thing at all. What if she liked what she saw? What if I lift up her tail and find that she is a dirty pegasus like me?
"H-hey captain, what's up-p?" Rainbow's voice cracked with nerves. Spitfire strolled into the room. She had already stripped of her uniform, and her coat was shiny and damp from a recent shower. She didn't look at the lump hidden behind Rainbow Dash's tail. "I noticed that you were flying a little stiff today, anything wrong?"
Rainbow let out a breath, she had not noticed. Recovering her composer somewhat, she turned to face her captain, the little ball of soft manure spreading itself across more of the fur that surrounded her anus, Rainbow's ass cheeks kneading the scat as she moved. "Naa, I'm fine, just a little stomach ache, I'll be as awesome as ever after a good night’s sleep."
Spitfire still looked concerned, "Well, just in case, take it easy this weekend and relax, I want you, and the rest of the team, to be in top condition next week, we don't want to lose our winning streak in the Equestria games now do we?"
"No, Ma'am!" Rainbow replied, she knew Spitfire liked the formality, even when they were officially of duty.
"Good, see you next week." Matters attended to, the Wonderbolt Captain trotted out of the changing room.
As Spitfire's orange tail whipped around the doorway, Rainbow Dash let out a sigh of relief. That had been close. Now, at last, she could head for home.
Trotting down the deserted corridors, Rainbow Dash was all too aware of the mess that she had made in her suit. However, with nopony around, her self-consciousness transformed into a feeling of sexiness. As she strutted down the hallways, she crisscrossed her hind legs. Not only did it give her hips an alluring sway, but every step she took caused the muscles in her butt to clench and unclench, squeezing and squishing the lump of faeces in an enjoyable manner. It was like a little toy she could play with as she walked, only much dirtier.
Opening the large front doors of the Head Quarters, Rainbow Dash stepped out into the cool evening air. Celestia's sun was setting, leaving an orange hew, quite similar to the fiery mane of her captain she noted, blushing slightly at the thought.
As Rainbow dash was about to take flight, a thought occurred to her. Nopony can see me now, and it's almost an hour flight back home, I could let out a bit more, some fun for the journey. A loud gurgle from her stomach sealed the deal.
Hidden in the cover of the doorway, Rainbow Dash spread her legs more widely this time as she squatted down, tail raised high into the air.
A small poof of gas signalled the arrival of the next load. This time it slipped out much more quickly than the first, and by the time Rainbow's messy ponut had managed to close around the log, what had meant to be a similar sized load as the first, had turned into a tennis ball sized horse apple. This new addition to the filth inside her suit bulged out, even with her tail, it would not be too difficult for some pony to notice the dirty stunt she had pulled.
However, to say that Rainbow Dash was displeased with this turn of events would be a severe divulge from the truth. The grin on Rainbow's face told the whole story as she wriggled her rump, feeling the soft sticky load sandwiched between her ass cheeks.
Reaching a hoof under her body, she ran it over the bulge, feeling the shape of the manure and the heat emanating from the fresh load. Pre-flight checks complete Rainbow Dash took off, leaving nothing behind but the soft sent of poop which was quickly carried off into the air by the cool evening wind.
To be continued...