The last jump you made was much higher than the rest, and when you landed, you bounced once again, but you weren't able to control the direction, and much to your dismay, you saw that you had just jumped over the 'edge' of Sheila's titanic asscrack. Being so light, you prayed you'd be able to make it to the other side and let this be a close call to sober up, but as gravity took its hold on you and you started going down, you realized that just wasn't going to be. Being the silent type in panic situations came to bite you when you would've needed it the most, as you remained quiet as opposed to screaming on your way down, which she may have heard. You more or less spaced-out as you fell for what felt like miles into the dark crevice, though you were at least thankful that her panties would be somewhere down there...

Sheila's crack was so vast it was only after more than halfway down it that you grazed one of its sides, and the colossal wall twitched in response as you slid down against it. She shuddered as she felt the lightest caress go down her enormous buttcrack, and that sent more, and more powerful shivers up and down her spine, and brought a pleasant tingly feeling all over her body. She also blushed a little, knowing what it meant.

"Ooooh... Naughty..." She said in an overly playful tone, and as she teasingly wiggled her hips, she failed to notice her cheeks lightly clenched.

You were still in a daze, when suddenly everything shook and forced you out of it. You were in pitch black darkness, everything around you wobbled like gelatin, and you felt two enormous waterbed-like walls press on you from each side.

"I didn't think you'd be willing to go there..." She then said
"Not that I mind..." She giggled almost like a highschool girl that just got a confession from her crush. But after a few seconds, it looked like her adult self stepped back in and took a deep breath.
"Still... I don't really think my booty smells too good right now, does it?" She asked.

And, as a matter of fact, she was right, too right, you could even say. Her crack reeked badly, and after what you heard about burritos, you guessed she had been already farting for a while. Still, as you were encased in her blubbery mass, you couldn't even move your arms to cover your nose.

"Listen... I get it that you like my big booty, even more than I first thought... but right now's not a good moment to go spelunking down there..." She said, and as if on cue her stomach groaned and gurgled, and she also felt an intense pressure near her gargantuan ass.
"So... since I can't hear you all the way over there, just move. Do something I can feel and I'll take it that you want out of there..." She said, completely oblivious to the fact that you were pinned in place by her sheer weight. You were actually trying to move with all your might, but the weight on you from all sides was simply too much. She patiently waited, but after roughly a minute, there was no answer. She blushed a little harder.
"Do... do you really not mind the smell back there?" She asked with a hint of hesitation. Another minute passed and there was no answer, and she could clearly feel him stay still between her massive cheeks.
'Maybe he even likes it... Well then, who am I to cut his fun short, right?' She thought to herself with a quiet giggle
'And to choose now of all times to go there... I did tell him about the burritos... And he perfectly knows what they do to me... Maybe he wants me to let loose on him, huh...' She kept thinking, and that thought turned her on in a way she hadn't felt before.

Still, before going down a potentially dangerous route, she decided to truly make sure he was up for what was coming next.
"Okay, last chance... Please move or do anything I'll feel if you want me to take you out of there..." She said, back in her more serious tone
"Or... don't move if you want to stay in there..." She added with a giggle. She decided to even give him more time to answer, but after 5 minutes, she felt nothing.

Meanwhile, you were trying your hardest to move and scream, but as soon as you opened your mouth you got more than a mouthful of her plentiful rear, and no sound would make it out of your mouth. Your limbs were simply encased by such weight that you weren't able to move them even an inch. The jiggly masses that engulfed you shuddered once more. Sheila's eyes widened

'D...Did he just kiss my booty?' she gasped, as she felt a very tiny touch, but unlike the others, there was a hint of wetness to it, and she even made out his small tongue after focusing for a moment. This was unexpected. You always reacted indifferently or negatively whenever Lillian broke wind around you, and while you were more restrained in your reactions towards your own mom, that was for fairly obvious reasons, but she didn't think you'd willingly subject yourself to that, and even more so given your current size. She then wondered if perhaps it was because it was her butt this time he was dealing with, and felt slightly flustered.

"Wow Blaise... You truly are a brave man..." She said with sincere amazement, and even a hint of respect to your newly perceived manliness in her books. The fact that she called you a man was already odd in itself, which meant she didn't see you as a kid anymore, much to your misfortune.
"I did tell you that I pigged out on burritos last night though... I thought that would've been enough of a hint..." She then said
"So, just to set things straight I'm letting you know what you just signed up for..." She said in an unintentionally ominous way that sent cold shivers down your spine.
"...You can probably guess that I'm feeling... gassy..." She said just as her stomach's groans intensified, and you could hear a stronger rumbling coming from deeper into her massive asscrack. The jiggly walls encasing you vibrated from the rumbling's own sheer intensity and that made you go pale. Then you felt your entire world shift from side to side, which meant she was likely wiggling her hips again.
"Are you really sure you want to stay in there? I know I asked before, but I still feel like you don't really understand what you're in for..." She said, and you struggled harder than ever to move or scream, but what little movement you managed to get done with your mouth caused everything to twitch and wobble again. You heard her laugh.
"Alright, alright... I get it..." She said with a slightly embarrassed laugh.
'Gosh, he really wants to have it...' She thought, mistaking your previous effort as more kisses to her enormous booty. Her stomach, which had been feeling in knots, and also like literal tornadoes were swirling inside, kept on groaning, but it a much more violent-sounding way, and she knew she wasn't going to be able to hold anything in for much longer.
"Okay... then, I think you should brace yourself hon..." she raised her butt into the air a little and wiggled it in a way that she meant as a warning about the impending storm.
"At least... they shouldn't be much worse than what Lillian's unleashed upon you, right?" She said, but you weren't quite sure if that was to you or rather to herself. You were also absolutely baffled about her lack of self-awareness, even you knew that the difference between her and Lillian's gas was huge! And that's not to mention she's ignoring your current size. But worrying about those things now was pointless anyway...