Sheila’s gigantic eyes widened in the distance. If she hadn’t just seen you shrink in front of her she wouldn’t know you were there. From her perspective you were like a tiny piece of dust, way smaller than she had previously dealt with.

“Oh my god, are you okay?” She asked you, waiting for a response. Of course even yelling as loud as you could, she couldn’t hear your voice.

“... It’s no use. I can’t hear a word you’re saying, you’re too small now. But what made you shrink again?” She thought about it, why were you becoming smaller when you were around her? What just happened? The last thing she remembered you saying before you suddenly shrunk was that you didn’t have a fart fetish…

“Oh. Ohhhhhhhhhh…” Sheila said out loud, her mouth slowly curving into a smile.

The first “Oh” she let out sounded good, like she had actually figured it out, but the second one just made you worry.

“I get it now. You keep shrinking because you’re repressing your inner desires.”

“W-What?!” you yelled out.

“I think the more you try to deny your fetish, the more your feelings become bottled up, until this happens to you. Whatever it is that’s making you shrink, it’s doing it because you keep saying you don’t have a fart fetish. The first time you shrunk you were even looking at my butt, weren’t you? You were probably thinking of all these dirty fantasies in your head until your body just gave in and let you act them out.”

You were stunned, absolutely flabbergasted. Thanks to what had to be the worst shrinking timing EVER Sheila was now totally convinced that you were actually a huge (tiny) pervert! This misunderstanding couldn’t be happening to you, not again like this, when your body was smaller than a pencil point. You didn’t have a clue why you kept shrinking, why any of this was happening, but if you were going to be shrunken at Sheila’s mercy you didn’t want her to go down this train of thought…

“I finally understand it now.” she said “You love being farted on, don’t you? Especially by my big giant ass. I bet you just can’t get enough of it, you cheeky little masochist.”

Sheila felt so glad she had finally pieced this little mystery together. It felt so obvious when she said it out loud. Maybe it was your body’s natural reaction to repressing your lust for so long or maybe it was fate’s way of helping you finally give in to who you were, but regardless it was the only explanation of why you kept shrinking when you did. Your little lies had her going for a minute there, that you ‘accidentally’ fell into her ass and still somehow managed to squirm your way down her giant butt crack. She had seen the way you’ve stared at her ass, even when you thought she wasn’t looking. The attraction was definitely there, and the squirms you made earlier in her butthole felt genuine.

Although Sheila wasn’t going to say it to you outright, she was really relieved that you actually had a thing for her gas. This whole time her body had been craving to continue the kinky fart play from earlier, and now she didn’t have to stop. She looked down at you and spoke again, her words dripping with the arousal of a fully mature horny woman.

“It’s okay Blaise… I can help you admit it. You can use my adult body to indulge in all your raunchy held-back fetishes. My ass is MORE than big enough for you now, right?”

Sheila moved to get into position, twirling you on her finger around her massive naked body. You watched in awe and in despair as she moved, her motions looked like distant mountains folding off the crust of the earth and bending up into the sky. Eventually she positioned herself so that her head was resting on the pillow and her gigantic ass was pointed upwards, straight towards the ceiling

You gazed down from her fingertip toward her awaiting ass. It was easily the biggest thing you had even seen before in your life. Sheila’s phat bubble butt wasn’t just humongous, it was like an entire planet in and of itself. Her great round booty curvature expanded far into the distance, beyond where you could even see, and yet as it moved its massive tectonic cheeks wobbled around with the weight of entire continents. In the center her vast butt crack opened up, deeper than the pacific ocean itself, a great chasm leading down to the most horrifying realm below. And you knew that’s where she wanted to put you.

“Please…” you whimpered, “don’t…”

Unable to hear your voice Sheila slowly spread her great blubbery ass apart with one hand, while delicately moving you in between her cheeks with the other. She had been anticipating this moment all night and now it was finally happening. She didn’t even mind that you were smaller now, in fact it made her more excited. The way she saw it, her giant ass and farts were going to be more massive than ever for you, although the difference in scale was actually much farther beyond her comprehension. All that food she ate wasn’t going to go to waste either. The gurgling that she felt inside her body indicated those burritos were already breaking down in her guts, becoming enormous bubbles of gas making their way towards her ass.

After a bit more effort in spreading apart her massive butt cheeks, Sheila finally managed to expose her awaiting butthole to you. A wave of maternal ass musk washed over you as her sweaty crack was revealed. The all-too familiar gassy scent felt even more potent at your new size. The huge finger your giant Auntie was holding you on approached her puckered hole slowly, letting the sheer scale of her orifice become clear to you. Despite having been totally smothered in her anal folds earlier, the way it appeared now felt like you could see even the most minuscule detail with perfect visibility. Her asshole wasn’t just the size of a house or even a street full of buildings anymore, now it was as large as an entire city.

Your eyes froze as you watched the ginormous backdoor come closer. It’s many wrinkles pulsated in and out, as if they were breathing with the giantess herself. Each single thick band of slimy flesh could fit your entire hometown on it and then some. It was such an incredibly massive landscape that it would take you a full day to walk across, yet there were so many other wrinkles just like it, and they were all clenched together. The tremendous mass of flesh eagerly throbbed at you, twitching with an unmistakable thirst for stimulation. You couldn’t help but wonder if Sheila was just so horny that she wasn’t thinking properly. It was possible…

“Do you see it down there?” she asked, with her finger pointed all the way up her ass crack. “My cute butthole’s been waiting patiently for this all evening. It’s all riled up and ready to go. I want you to enjoy yourself down there, just like you were doing before. Don’t worry about anything, just have a good time with my gigantic asshole and farts, okay?”

Her colossal sphincter winked at you hungrily, barely containing her excitement.

“Now, let’s get back to where we left off…” Sheila said, and then she pressed her finger flat against her asshole.

You were crushed for a terrifying moment, and then Sheila’s finger retracted, leaving you back in the smothering darkness of her anal gateway. Almost right away her city-sized butthole started rhythmically throbbing from under you, pulsating greedily as its favorite tiny plaything was returned to it. As you held on for dear life you noticed that the sticky sweat and natural oils from last time were much more of an issue now. Your body was shrunken down so small that the rank goopy substance coating Sheila’s anus was all the way up to your knees, and as you toppled over you were practically bathing in the juicy filth. Worse yet, as her mountainous butthole throbbed and clenched you could actually HEAR the sounds of it smacking its massive wrinkles together. Her huge horny anus was making wet schlorping kissing sounds at you, contracting and masticating its giant fat wrinkles together as it twitched with arousal. The real kicker is that it wasn’t even throbbing that hard yet, this was barely quivering compared to what it could really do.

As you tried to maintain your stability you quickly noticed that the sticky oils on Sheila’s giga-sized anus were clinging hard to your body. You were essentially stuck in place, as if you were caught in a pool of glue and unable to move. You couldn’t do much of anything at all, your body was shrunken down the point where you were absolutely powerless. There wasn’t any way that you could crawl out from her ass now, not at your size, and of course no one else knew you were trapped down here either. It was dark and you were scared, at this point nothing could stop Sheila’s giant ass from having its way with you. The words she said before repeated back in your mind. She said she didn’t mind if you went all the way inside…