>Cheerilee gulps.
>The pressure in her gut is becoming harder and harder to contain.
>”You okay, Miss Cheerilee?”
>”Y-Yes, thanks, Sweetie. A-as I was saying, there are three fundamental types of matter. I-If you’ll look at the diagram here. Solid... liquid...
>Her teeth clamp together as a warm plume of silent wind brushes against her tail. She crosses her hind legs and lowers her tail to cut off the flow.
>”... and gas.”
>Her eyes scan the classroom; the fart was quiet enough that nopony has heard it, but that doesn’t stop them from...
>Cheerilee lets out a coughing splutter. The smell hits her out of nowhere.
>It’s like expired dairy and hot, disgusting garbage.
>”Miss Cheerilee? Are you sure you’re okay?”
>She swishes her tail to dispel the odor and wipes a tear from her eye.
>”Y-Yes! Now, if you little fillies and colts will turn to page four, and do the exercise there.”
>Her flanks fall softly onto her cushioned chair.
>She watches as the students lower their heads into their books. The room falls into a deathly silence; so quiet even a feather falling would attract some attention.
>A low groan bubbles somewhere inside her, slowly edging further down.
>She bites her lip, distributing her weight from one buttock to the other, and, with less than a push, eases out a long, gentle purring fart.
>The cushion soaks up the warm stream of gas, and half-muffles the sound, but it’s still there.
>Deciding she’s let enough out for now, Cheerilee settles back down, chair protesting under the weight of the mare.
>Now, she waits. Waits and watches.
>After only a few seconds, she’s hit by that same sour stench again; the dense, humid gas enshrouds her and she tries to maintain an unbothered facade; a steely, composed expression that’s on the verge of breaking entirely.
>Sniff. The air stings the back of her nose like menthol, and unsettles her stomach, but she has to grin and bear it.
>With unwarranted confidence Cheerilee leans to one side again, using her hoof to peel open her cheek and let a hot, silent, swampy fart pass out in an invisible steamy fog.
>”Eww!”
>Cheerilee panics.
>”Hey, Miss Cheerilee! Somepony ripped flank!”
>Diamond tiara fans her hoof around, her tongue stuck out in disgust.
>”W-Well...” her voice is trembling, “Please save it for after class, whoever that was. Have some manners.”
>”I don’t even know if I can WORK with that! It’s disgusting! I’ll bet it was little miss farm pony over there!”
>”Hey! It weren’t me!” Apple Bloom protests.
>”Huh. Likely story. Don’t think we haven’t all heard about your sister and her little fart contests with Rainbow Dash!”
>”That’s not true and you know it! Miss! Diamond Tiara’s spreadin’ misinformation!”
>”Not as bad as what you’re spreading, rank flank! Hey! That has a nice ring to it! Rank flank! Rank flan-“
>”Girls, be quiet!”
>Cheerilee stands at her desk, hooves pressed down authoritatively.
>She quickly realizes, though, that this new position is only encouraging another release, and promptly sits back down, hind legs crossed and face filled with shocked embarrassment.
.>”J-Just... get on with your work! All of you!”
>With a few grumbles the students get back to reading, muzzles all covered by hooves.
>”Hey, Miss Cheerilee! Could you help me with this?” Scootaloo waves her arm up above her head.
>”Can’t you try and figure it out by yourself, Scootaloo?”
>Another low stomach noise. It’s begging to release, and this time it feels like a big one.
>”I don’t understand it! Can’t you just show me how to work it out, and I’ll do it myself from there?”
>”O-Okay.”
>Her smile trembles as she stands up. Already the gas is pressing against her colon; fully inflated and sending painful cramps through her body.
>With careful, calculated steps she makes her way across to Scootaloo’s desk. Not too far. If she can just hold it for a few more seconds.
>”What seems to be the problem?”
>She leans forward, Scootaloo starts pointing towards the question in the book, and then, her grip loosens.
>She hears it before she even works out what it is; a loud fanfare of wet, cacophonous flatulence.
>It builds in volume and intensity, rasping and spluttering on and on until, after about eight full seconds, with a squeaky pinch of her sphincter she cuts it off.
>Her heart falls in her chest.
>She peers anxiously over her shoulder, where Diamond Tiara is frozen in place: her face fallen and eyes as wide as saucers.
>”Uhm... heh... class dismissed?”