Emily would lean forward and grab onto her kneecaps as she would grunt and whine. Kicking her legs frantically as her asshole would bulge our considerably, a ginormous, bulgy turd would sneak its way outward, straining against her fat asshole. Her meaty ass cheeks jiggling furiously as Emily would gasp for air above. The log would just grow and grow continuously, seemingly endless as the completely massive shit-stick would reach halfway into the bowl. Emily would feel that her new creation didn't want to leave it's parent, as she began to lift her cheeks in an attempt to make it release into the bowl, only to have it repeatedly smack against her cheeks in the process.
An expression of annoyance would wash over Emily's face as she'd lift her ass from the seat, pushing one more time before slamming her gelatinous behind back onto the toilet with such force that she finally managed to dislodge the turd from her ass.
Alex, however, would look upwards as his eyes were glued to the mammoth behind as it wobbled furiously above him. His eyes widened and skin turned white as she saw the booty come crashing back down in front of him, the sheer wind force was enough to push him backwards, slamming his head against the toilet lid which was angled enough to make him bounce upwards, lobbing above Emily's red, sweaty face as he'd shortly after find himself free-falling, hitting his head square onto her left thigh, which was soft enough to not cause any permanent damage to his body. He'd still slide forwards though, finding himself grabbing onto one of the few hairs on her leg as he'd slide down the front of her calf, quickly rushing down it's length as her foot caused him to slide onto the tiled floor, stopping just by the door of the stall.
Alex would shake his head rapidly, barely able to comprehend what just happened, he'd look in front of him, thanking whatever deity her could think about due to his freedom.
He'd look back over his shoulder, seeing Emily's eyes closed as she bit her lip, a vicious growl escaping her lips as a torrent of liquid farts would explode out her rectum, she would kick her feet like a spasm and accidentally kick her purse over, causing it to tip over as you'd see plenty items slide into the next stall over.
He'd shiver, crawling a few feet away just to be safe before he'd sit down to think, wondering what he would do.
Next Stall.
One of the items which slid into the next stall was a cellphone, which Alex could use to call for help, though there was plenty commotion going on outside, which could make this troublesome.
Main Door.
Alex figured he'd try his luck with the bathroom door, although closed, and sealed tight enough so he wouldn't be able to get out on his own. Which was probably just to keep the ass stench contained. But if he'd wait for someone to enter, maybe he could slip out fast enough.
Mysterious Hole.
Alex's eyes would dart to the other end of the bathroom, noticing a small hole inside it which seemed custom made for his own size. Probably the work of rats, though it'd definitely be less risky than the other choices. Where he might end up is unclear, but hopefully it's not a place he'd regret. (Yeah, right~)