"Bottom's Up, Going Down!" she said as she closed her eyes, put the flask to her thicker lips, and began to drink, envisioning it making her smaller with each sip, and as she pictured it in her mind's eye, it became reality. Roly Poly watched as Jenny began to reduce in front of his eyes, her fat form slipping downwards towards the ground, her already loose clothing sliding off her entirely as she glugged down the contents of the flask, having to use two hands to keep it up.
"Why don't you think about throwing in some clown looks too, just to complete a look!" He suggested, and in her mind's eye, she saw her self donning several clown characteristics. He watched as these mainfested in her real look as she continued dwindling. Her hair became a red afro, curling and poofing up with a FWOMP sound, while her feet began to grow and lengthen, getting long and wobbly and thick. Her hands also inflated a bit, looking a bit more like cartoon gloves than fingers. She was now less than a foot tall and still going, still chugging the liquid, which seemed endless.
Her nose swelled up and turned red, but it kept a somewhat human shape, despite being much larger on her face than a nose had any right to be. Her lips swelled into a big smile, which sipped more from the flask.
Soon she could no longer hold the flask and it clattered to the floor, not a drop spilling as Roly Poly collected it and watched her finish her decent into tiny-ness. He walked over to the pile of empty clothes that now held a tiny four inch tall obese clown looking up in awe.
"It worked" she squeaked, her voice sounding cartoonishly shrunk.
"Of course it did! My stuff always does! Now then, Teensy, let's get you out of those clothes and somewhere safe." he said picking her up and sliding her into the front pocket of his overalls, right next to his silly pen, and a stick of gum that was almost as tall as she was. She peeked her head out of the pocket and pulled herself up, hanging on with her arms.
"Neato! He'll never find me here!"
"Exactly!" Said Roly Poly.