"Well," says Sheila, wiggling her eyebrows. "I could do that. But I'm not so sure how safe that would be. I was thinking you could ride somewhere a little more secure. Like… my panties?"

"Your..." Hearing this, you can't help going white. "Y-your panties?"

"What, too forward?" Sheila grins, turning around to give you another unrestricted view of her giant, curvy rump. "I mean, after that one time you slept over a couple months ago..."

Of course, you know exactly what Sheila is talking about. Of all the pranks your friend Lillian has ever played on you, she really outdid herself with that one.

The night itself was totally uneventful — ordering Mexican food and watching a few hours of anime — but the morning after was one of the most embarrassing moments of your life. Shortly after getting home from your little sleepover, your mom got a call from Sheila, who explained that several pairs of her dirty underwear had inexplicably gone missing since you'd left their house. When your mom came up to your room to ask if you knew anything about it, she found your overnight bag overflowing with strong-smelling panties. While this was obviously all Lillian's doing — she'd volunteered to pack your bags before you left, and you'd accepted her offer without a second thought — you failed to get your mom on the same page. Then, to add insult to injury, she decided the most fitting punishment would be sending you back to Sheila's house to return her underwear in person. 

"I told you," you say, for the tenth or twentieth time, "that was all Lillian-"

"Ah ah ah." Sheila shakes her head, still smiling. "There's no need to be modest, sweetie. It's perfectly natural for a boy your age to have certain... feelings around a woman like me."

As if to highlight everything you might be having feelings about, she gives her ass another good slap, sending her big, thick cheeks jiggling enticingly. 

"I know that," you say, stumbling over your own words as your vision fills with Sheila's bodacious booty. "It's just that... wow, fuck..."

"Your mouth is saying one thing," chuckles Sheila, eyeing the stiffness in your pants. "But your second brain is saying something else. So what's it gonna be?"

"I..." Staring up at the giant, mature Brazilian amazon, you're still not quite sure you're totally on board with this plan—but some small part of you is keen to stay on her good side, just in case. "Okay, fine. Let's do it."

"That's the spirit," says Sheila, stooping down and extending her hand toward you. "Now, all aboard!" 

With a final deep breath, you carefully climb onto Sheila's palm. As her huge, soft fingers curl around you, it's hard not to feel another pang of uncertainty—especially as she moves her hand to the waistband of her huge, lacy pink underwear. 

Before all of this, Sheila often used to joke that she could probably fit your entire head in her butt crack. Now, it looks big enough for you and at least fifty of your closest friends. Each of her cheeks is at least the size of your house—and together, they seem to radiate with feminine power. Dangling just a few feet away, you can't help feeling humbled. 

prrrrtttttttt

"Whoops!" Sheila giggles, fanning her fumes away from you with her other hand. "Sorry, sweetie! I think there's more where that came from."

As another wave of sulfuric air washes over you, all you can do is cover your mouth and nose—which limits your ability to push back on what happens next. 

"Anyway," says Sheila, "here goes!"

Without another word, your giant honorary auntie pulls her underwear back with her free hand and carefully presses you between her cheeks. The result is nothing short of a sensory overload. All you can see is darkness, all you can feel around you is warm, soft, overwhelming flesh, and all you can smell is sweat—although as Sheila forces you deeper and deeper into her crack, a new, far more sour and earthy aroma quickly begins to override that. In a matter of seconds, you're right up against her colossal asshole — now roughly the size of a tractor tire — and your nose feels like it's burning. 

"Ooh," coos Sheila, feeling your tiny face pressing into her rancid pucker, "someone's enjoying themselves!"

As you struggle to avoid getting your whole head sucked into Sheila's asshole, enjoyment is the farthest thing from your mind. Already, you're kicking yourself for not turning down this offer when you had the chance. Now, it seems like you're totally at your giant auntie's mercy for the foreseeable future.

"Alright," says Sheila, giving her cheeks a playful clench around your comparatively tiny form, "let's make tracks!" 

*

While you're unable to make out much of what's happening beyond Sheila's cheeks as she walks back into town, the sounds that manage to get through your fleshy prison certainly paint a picture.

As the giant Brazilian MILF stomps her way into the center of Storm City, most of the area's normal-sized residents scatter before her like bugs. The only ones that stay are mostly men — though she notices a few women among them, too — risking their lives to get close-up photos and videos of her colossal curves in person. Sheila, being Sheila, of course, can't resist stopping to pose for them several times, slowing your journey into the city considerably. 

"You want another couple from the back?" Shaking her hips for a group of photojournalists clustered on the roof of a nearby midsize building, Sheila giggles. "Just wanna make sure you boys get my good side, y'know?"

Still stunned beyond words to be talking to the giant, drop-dead gorgeous MILF currently breaking the internet worldwide, the photographers respond with several enthusiastic thumbs-ups. 

"Cool beans," says Sheila, turning around and bending over, more or less mooning the whole building. "Lemme know when you're good."

BBBRRRRAAAAAAAAAPPPPPPPP

Just before the photographers finish setting up their shots, another colossal fart slips out of the mature giantess's ass, washing over the whole building, breaking windows, and knocking all of the people on the roof clean off their feet. Down in her ass, you get the brunt of the impact more than anyone—although, perhaps owing to all the farts you've smelled at the hands of Sheila, Lillian, and all the other supernaturally gassy women in your life over the years, you seem to be relatively unaffected compared to everyone else.

"Oh... oh dear!" Putting a hand over her mouth, Sheila gasps at the devastation she's unintentionally wrought. "I am SO sorry about that, everyone. Are you alright?"

Fearful of angering the walking superweapon, the few journalists still conscious respond with another round of thumbs-ups—albeit with significantly less energy than last time. Seeing that all of them are still breathing, Sheila lets out a huge sigh of relief. "Thank goodness... well, on that note, I suppose I should get going. You all have a nice day now, alright?"

Without waiting for a final response from the group on the roof, the 250-foot Brazilian MILF turns and continues on her way. By now, most of the streets are mercifully free of people and cars—and once videos of Sheila's unintentional gas attack on the photographers start circulating online, most of the other stragglers decide to play it safe and leave the area. When she finally gets downtown, the place is more or less deserted.

As Sheila steps over to survey the butt-shaped crater she left in Storm City Stadium this morning, she registers a strange buzzing sound in her ears—one instantly familiar from her first giant-sized trip downtown. Of all the camerapeople intent on documenting her figure up close, she's already finding the ones in helicopters to be the most annoying. At her newfound size, they're almost like mosquitos—but louder, and much more persistent.

Spotting the machine behind the noise, a large news helicopter filled with cameramen, she sighs. "Hey, buzz off, why don't you?" 

"We're just doing our job, sugar tits." The helicopter's response comes via loudspeaker—a sneering, smarmy young man who seems to be the pilot. "Now turn around and show me that ass!"

At "sugar tits," Sheila scowls. "What did you just call me, young man?" 

"The fuck does it matter?" snaps the pilot. "Ass time. Now."

Feeling a perfectly timed gurgle in her stomach, Sheila allows her scowl to become a smile. "Alright, if you insist."

Turning around and bending over, the mature giantess waits until the helicopter starts to move over her cheeks. It's all she can do to hold back the bubbling buildup in her sphincter until the perfect moment, and you can feel the pressure mounting from your perch in her crack the whole time. Then, just as the comparatively-tiny machine gets right over her asshole, she lets loose. 

BBBBBRRRRRRAAAAAAAAAAAPPPPPPPPPP

Once again, a huge blast of warm, stinky air explodes out of Sheila's ass, washing over you point-blank and filling the air around the helicopter above her. Inundated with sulfuric stink, it only takes the pilot a few seconds to turn tail and fly away, leaving the two of you alone. Standing up to watch the tiny flying machine bobbing and weaving away into the distance, everyone on board visibly loopy under the effects of her gas, Sheila grins.

"Let that be a lesson to you, sweetie," she says, giving her cheeks another affectionate clench. "Never talk to a woman like that, ever." 

"G-got it, S-Sheila," you say, feeling pretty loopy yourself. 

Before the mature Brazilian giantess can say more, a telltale noise cuts through the air—the unmistakable sound of more giant footsteps headed your way. 

When Sheila turns around toward the source of the noise, her jaw drops. "No way..."