The Equestria Girls (except Rainbow Dash) slept in a bedroom that night. This shared bedroom had no bathroom, so if they needed to go, they'd have to walk to the bathroom at night. Fluttershy had woken up at 2:00 in the morning really needing to pee. She quietly tiptoed to the bathroom, afraid that Aria would make her do something or punish her, though Aria was fast asleep. She barely made it, and got back to sleep in her bed.

At 7:00 in the morning, the girls awoke to the sound of a gong run by Sonata.

"Sunset, Rarity, Aria wants you in the mud field!" she said. "Follow me!"

Sonata led Sunset and Rarity to a field made entirely of mud. It was the size of a football field. Aria was relaxing on a beach chair, wearing her pajamas: Short purple shorts and a matching midriff tank top.

"Rarity, you plow the mud field," said Aria. "Sunset, provide her with water, and give her some beans at noon."

"What is this mud field even for?" said Rarity.

"It's for my trio of pigs," said Aria. "Our horse, Fartsparkle, needs her exercise so she chases the pigs around. Try not to get in her way!"

The mud plow was in the center of the mud field. Rarity reluctantly walked over to the plow and put the harness on. She didn't want to do this, but she didn't need Aria to tell her what would happen if she didn't - she knew it wouldn't be pleasant!

Rarity started plowing the field. The plow was heavy, but too heavy, although Rarity estimated it would take her hours to finish this. She was sweating like a pig in the heat, so Sunset would give her a glass of water every five minutes, and drink some herself.

"Can I go to the bathroom?" said Sunset. "I haven't gone to the bathroom all morning and I really have to go!"

"Hold it until she's done," said Aria.

At noon, Rarity was three quarters done while Sunset was holding herself and doing the pee pee dance. By now, Rarity needed to pee pretty badly too, since she had to drink lots of water.

Pinkie Pie and Applejack came walking over, each carrying two heaping plates of beans. Sunset was currently giving Rarity her glass of water, so they walked into the mud field. Pinkie Pie gave her plate to Sunset as she was walking back to the grass, and Applejack gave her plate to Rarity.

Once Rarity was eating the beans, Pinkie and Applejack turned around to walk back to their rooms, since no other task was required of them, but they tripped over a pig and fell in the mud.

Then, Sonata brought in the horse, Fartsparkle. Fartsparkle ran over and kicked mud all over Pinkie and Applejack, drenching them completely.

Pinkie let out a sloppy wet fart, and giggled. "I think I just made my shorts even dirtier!"

As Fartsparkle chased one of the pigs around, she ran just in front of Rarity. Rarity stopped, putting both hands on her crotch, for she had nearly lost it there, leaking a bit into her underwear.

Rarity stood still for about a minute, desperately trying to hold it in, while Sunset was even more desperate. Aria took little notice of Sunset; with a groan, she stood up and walked over to Rarity. She whistled for Fartsparkle to walk over to her as well.

"Why are you slacking off?" said Aria.

"I need to use the bathroom really badly!" said Rarity.

Aria grabbed Rarity's left foot with one hand and lifted her into the air upside-down. Rarity's light blue panties were clearly visible. She accidentally farted loudly.

With her free hand, Aria slapped Rarity's rear end five times, and then threw her facedown into the mud.

"Fartsparkle, sit on her!" Aria commanded.

Fartsparkle sat on Rarity's butt. Rarity tried her hardest to get up, but the horse was too heavy. Eventually she could hold it no longer and peed, sighing of relief. At least she was in the mud already so it hardly mattered that she was peeing herself.

Then, Fartsparkle farted on her five times. Her farts smelt horribly foul, and the fifth fart caused Rarity to faint.

Fartsparkle resumed chasing the pigs, while Sunset continued to hold it in as long as she could.