Author's Notes:

Of course Lightning Dust is wearing her same outfit from her first chapter, and will be unless I say otherwise. If you forgot: Short skintight teal shorts and a matching midriff tank top.

And if I'm ever inconsistent as to when they wash, we'll say they either washed a bit earlier or later, or else got really dirty at some time.

While Adagio was having lunch with Sonata, Pinkie, and Sunset, Lightning Dust was pacing back and forth.

An idea had just occurred to her as to why Rainbow Dash won all her races. Perhaps it was because she smelled bad no one wanted to go near her, and as long as they were behind her, her smell would slow them down. Especially if she was farting a lot.

A devious grin spread across Lightning Dust's face. She was usually disgusted at the idea of smelly girls. But, if she became one herself, she wouldn't have to be disgusted by them, and she'd have equal chance of winning the race, both because she'd slow them down as much as Rainbow Dash did, and because if she smelled as bad as Dash, she'd be immune to her stench and therefore she'd kick her dirty ass!

...

Three days later, Lightning Dust attended one of Rainbow Dash's races. She hadn't washed since then and was starting to smell. Rainbow Dash won her race, as usual, and Adagio placed sixth. As they walked away from the track having claimed their prizes, Lightning Dust walked over to them.

She walked past Adagio first, got up close, and sniffed her. "Phew, you smell bad."

"Are you here to give me shit again?"

"Not this time. This time I want some advice on how to become a smelly girl."

"That's better, I guess. It is kind of fun."

"How often do you wash?"

"Once a week."

Lightning Dust sniffed her again. "I think half your smell is pee."

"Probably. I wet myself whenever."

"I don't want to wet myself all the time. How can I smell as bad as Rainbow Dash while keeping my shorts dry? Not counting sweat, of course."

"I can answer that," said Rainbow Dash, who was walking up to them. "I wash once every two weeks. And I don't use soap, except when washing my hands. I do use shampoo, though. My head gets really itchy if I don't. I use dry shampoo every day I don't shower. For best results, don't wash your outfit unless it gets really dirty. Even though on the occasion I do get it wet, it doesn't stop smelling bad unless I use soap."

"And you don't wet yourself a lot?"

"Usually I don't. It has happened a few times, but most of the time I find a toilet or just find a bush, pull my shorts down, and pee outside."

"All right. I got it."

"Wait. You used to hate me for smelling bad. You thought I was really disgusting. Why do you want to smell bad now?"

"So I won't be bothered by your smell." This was partly true.

"Rarity's got air freshener for that, but, if you want! It'll be nice to have another smelly girl as a friend."

"I don't know if I'd call us friends yet, but, whatever!"

Rainbow Dash farted loudly, and chuckled. Lightning Dust smirked. She was sure Rainbow's flatulence contributed to her smell as well.

"Oh, out of curiosity, did Indigo Zap tell you how she got to smell like that?"

"She washes once a month at most, she wets herself whenever, and she doesn't use toilet paper."

"Yeah, I'm DEFINITELY not gonna want to smell like her." However smelly Lightning Dust wanted to be, the idea of not using toilet paper was too disgusting for her no matter what.

...

That afternoon, Lightning Dust bought some fart powder. She also got lots of beans, because they were high in protein and they'd make her gassy. She decided she was going to fart as often as she could!

Today she cooked a big plate of beans, so there was no need for fart powder. But, she planned to put fart powder on anything she'd eat that didn't make her particularly gassy.

Once she wolfed down her beans, she waited patiently. And then...

PPPPPPFFFFFFFRRRRRRT! BBBBRRRRRT! PPPBBBLLLAAAAAP!

Lightning Dust chuckled as three loud, wet farts made their way out of her rear. Afterwards, she let loose with another set of explosive farts. Then, she paused for a moment.

FFFFFFFFFFFFFRRRRRRRRRRRRRRRRRRRRRRT!

Lightning Dust sighed in relief, and slapped her butt lightly.

Once she was done farting, she pulled her shorts off, exposing her black panties. She sniffed the butt of her shorts and winced slightly, but felt satisfied. For her shorts smelled like farts, as well as the sweat that had accumulated over the past three days. She had, of course, slept in these shorts too, rather than her usual pajamas. She put her shorts back on and walked to the basement to exercise.

...

Over the next several days, Lightning Dust ran several laps in the summer heat, avoiding the rain whenever possible. She drank lots of water, making sure she sweated and farted as much as she could. She couldn't believe she was becoming the thing she hated most, but she had to admit, it was kind of fun.

Finally, it was two weeks since she stopped washing. Lightning Dust woke up in her bed to her own smell. She sniffed her armpit and recoiled slightly, but after another sniff she let out a sigh of satisfaction. She smelled awful. Just the way she wanted.

Today she'd finally beat Rainbow Dash!

She had made sure to get Rainbow's phone number so she could challenge her whenever she wanted.

"Hello?" Rainbow Dash answered after Lightning Dust called her.

"Rainbow Dash! It's me, Lightning Dust! I'm pretty sure I smell as bad as you now, and I'd like to race you again!"

"Sure. I'm entering the race at 11:00. You can enter if you want."

"On it!"

She paused to take a drink of water. She had put fart powder in all her water bottles, and she never forgot to put more in when she refilled them. Then she ran out her front door.

...

Lightning Dust met with Rainbow Dash, Adagio Dazzle, and Applejack at the big racetrack.

"Howdy, Lightnin' Dust." Applejack walked over to her to shake her hand. She sniffed her up close. "Phew! You smell as bad as Rainbow Dash!"

"I was hoping I did!" said Lightning Dust proudly. "Now I have a chance of winning!"

"Smellin' bad has nothin' to do with it," said Applejack. "Adagio and ah smell bad and we don't always place second."

"Say what?"

"No, I just win cause I'm really fast, and a really good athlete!" said Rainbow Dash. "Besides, you have to be pretty close to me to smell me. Or in an enclosed space."

"We'll see about that!" said Lightning Dust. "Besides, you two only smell half as bad as Dash and I!" She paused to let out a boisterous fart.

"Oh my," said Rarity, who was watching from the sidelines. But she was getting used to seeing girls fart like that.

"Wow, you've changed since I first raced you," said Rainbow Dash. She chuckled a bit. "You might need to change your shorts after that!"

Lightning Dust felt her butt, looking a little nervous at first. "No, that was just a fart."

"Gotchya!" said Rainbow Dash.

"Very funny."

Lightning Dust sniffed Rainbow Dash. "You are a lot easier for me to smell now!"

They stood at the start of the racetrack. At the sound of the horn, they ran.

Lightning Dust and Rainbow Dash were neck in neck at the front, occasionally one of them pulling ahead.

"Not so easy when you're not the only smelly girl in the race, is it?" said Lightning Dust.

"I told you it doesn't matter! I'm just real fast!"

Lightning Dust farted in response.

Adagio was in sixth again. She had to go to the bathroom, so she peed as she ran. She enjoyed the convenience of being able to pee whenever. As long as she wasn't sitting on something she didn't want to ruin, or standing on a carpet her friends couldn't easily clean. She often kept a towel handy for sitting on, following Wallflower's advice on how to wet respectfully.

As they neared the finish line, they started to run faster. Lightning Dust pulled a bit ahead, but then Rainbow Dash got ahead, winning the race by a foot.

"And once again, the winner is Rainbow Dash!"

"What?" Lightning Dust sat down, panting and dripping in sweat. "How could I lose? I'm immune to your smell now!"

"That's what we've been trying to tell you," said Adagio. "Her smell has nothing to do with her performance."

"All right, fine." A puddle of sweat was starting to form under Lightning Dust's butt.

"Good game, Lightning Dust," said Rainbow Dash, reaching down to shake her hand, and equally soaked in sweat.

Lightning Dust hesitated, and then shook Rainbow Dash's hand. "Sorry for thinking you only won your races by smelling bad."

"It's all right."

Lightning Dust sniffed her armpit. "I should probably rinse today. Are you sure it won't make me stop smelling bad?"

"Trust me, it won't. It'll just keep you from smelling like Indigo Zap."

"Then, I'll definitely rinse today."

"Do you really smell like Rainbow Dash now?" Adagio sniffed Lightning Dust closely. "Phew! Yes, you do! I've been a smelly girl for some time now and you already smell worse than me!"

Lightning Dust blushed and giggled. "I can still smell the pee on you."

"It must be cause it's not part of your smell."

"Sometimes ah go in mah shorts when I'm workin' at the farm," said Applejack. "Usually only then, and ah usually dry off in the sunlight."

"Why does that not surprise me?" said Lightning Dust. She let out a long, wet fart.

"Lightning Dust!" said Rainbow Dash.

"Excuse me?"

"I'm just kidding." Rainbow started to laugh, evidently having held it back until now.

"Well, now that you know the truth, you don't have to be a smelly girl anymore," said Adagio.

"Actually..." Lightning Dust sniffed her armpit again. "I kind of like it. Now I can see why you do, too."

"Awesome!" said Rainbow Dash. "You're still gonna fart a lot too, right?"

"Of course! It's fun to fart! We should have a farting contest!"

"We totally should!"

"How about we fart in each other's faces, and whoever faints first wins!"

"No. We smell too bad to be bothered by anything that doesn't smell as bad as Indigo Zap. Let's just measure them by length like I always do with Pinkie, Sunset, and Indigo."

"Length it is!"

Lightning Dust released a short but boisterous wet fart.

"And try not to soil yourself," said Applejack. "Trust me, it's mighty unpleasant."

Lightning Dust felt her butt again. It was wet, but only with sweat.

...

PPPPPPPPPPPPPPPPFFFFFFFFFFFFFFFFFFFRRRRRRRRRRRTTTT!

Lightning Dust sighed in relief and then chuckled, patting her butt lightly. This was her longest fart yet!

"36 seconds!" said Adagio, who along with Applejack was timing the farts. They sat next to each other, not caring how bad they smelled, because they smelled the same. Though, Adagio smelled a little more of pee because she wet herself more often than Applejack.

"Wow, that beats my record from my farting contest with Indigo!" said Rainbow Dash once she stopped laughing.

"Ha!" Lightning Dust slapped her stinky rear end. "Wait, what's your record?"

"33 seconds." Rainbow waited a while, and when she was ready...

BBBBBBBBBBBRRRRRRRRRRRRRAAAAAAAAAAAAAAAAP!

"Whoa!" said Rainbow Dash, fanning the air with her hand. "What was my time on that?"

"34 seconds," said Applejack. "Sorry Rainbow."

"It's all right," said Rainbow Dash. "There's nothing at stake here this time. It's just for fun!"

Lightning Dust was amazed at how good a sport the competitive smelly girl was being. Maybe she should follow her example.

"Besides, it breaks my record!"

After several more farts, none of which were longer than 30 seconds, the two smelly girls ran out of gas.

"Yes! I finally beat Rainbow Dash at something!" said Lightning Dust. "I just never thought it'd be a farting contest."

"Good game," said Rainbow Dash, holding out her hand.

Lightning Dust shook her hand. "I... hope it was fun?"

"It was! I love farting! Especially for that long!"

"Well I'm not gonna stop eating stuff that makes me fart! And if it doesn't on its own, I'll put fart powder on it!"

"I don't usually do that, but I do usually eat beans. And I can't wait to race you some more!"

"Neither can I!" She turned around. "Rump Bump?"

Rainbow hesitated. "Sure."

They bumped their dirty rumps together, and then rubbed them a little. Not for sexual reasons, but because of how dirty they were, and as a symbol of their farting contest. Rainbow could get used to this.