"Do you know what I do to those who make fun of my weight?" the fat woman said to you with a mean-looking smirk.
"W-what?" you stammered in genuine confusion. "Ma'am, I just work here, all I said is that we might need to look for a rack with pants a few sizes bigger, I'm not trying to offend you, just trying to help. Trying to be...realistic."
"Mmm-hmm," she cooed with an ominous chuckle. "You and everyone else trying to be so 'helpful.' Always some excuse..." She made a flowing motion in the air with her hands, and your vision began to distort.
"W-wait, how...what...?"
"You'll need pants more than a few sizes bigger when I'm through with you...but then, animals don't don't have much use for pants. Soon you'll learn what it truly means to be fat," she cackled. "Enjoy your permanent Congo vacation...and say hi to the others, I do wonder how well they're adjusting!"
As your head swam and sight dimmed, the last thing you saw was her cruel grin as she waved her pudgy fingers goodbye...
You awoke to a rank, earthy stench, and the sounds of jungle birds screeching all around you. You groaned, and a deep bellow rang out from somewhere nearby. You were dimly aware of a wet, slimy sensation encompassing your body, like a sunken mattress saturated with liquid...you tried to roll over and found it incredibly difficult, as the muck sucked at your skin and held you in place...or was there something else making it hard to move?
Blinking, your eyes adjusted to the light to find a sprawling grey mass in front of you...a mass that rose and fell with every breath...your mass. Somehow, impossibly, you'd become a gigantic blob of a creature...a noticeably female creature, with bloated, heaving breasts that dominated your view, with an expanse of a belly beyond. With effort, you raised your fat thighs, freeing them from the muck below with a squelch. The stench from earlier grew stronger - was it the newly-exposed mud, or was it coming from you? As you peered down at your undercarriage, you saw something bobbing between your legs...relief quickly turned to dismay, as it became clear the protrusion wasn't your dick. It was a short, ropey tail, dangling beyond your pudgy pubic mound...your pussy. With another groan, it became clear that the rumbling bellow you'd heard before was your own. Your face was massive, two bumpy nostrils visible at the end of a broad snout...
You were a hippo. A fat, disgusting hippo, relegated to the unknown depths of some African jungle.
Before you even had time to panic, a bellow from somewhere nearby startled you, a sound similar to your own. The hulking shape of another hippo rose from the muck in front of you, gazing in your direction...you instinctively knew this hippo was male, and his intentions were clear. With a strained bleat, you waggled your enormous legs, struggling to scramble backwards. This was too much, there was no way...but with each rumbling vocalization from the male, something in your new anatomy fluttered, a twitch, a new itch...despair and desire fought for control of your new existence, and through it all you wondered why...why had you caught the ire of that woman, why you, why here?