"Alright, I've got a tail. Where to next?" the spaded appendage lightly flicking in the air as she looked about, eyes focusing on a nearby vending machine.
She was thirsty. She wasn't before but she was now. And she wanted a drink, badly. Racing up to the machine she put in another quarter, almost desperate for something to quench her sudden and all consuming thirst. "Please provide desired species." the machine droned, a light female voice, mechanical and curious.
"Imp" said too quickly as Amy began tapping her foot, a little fidgety as a clear bottle of pink soda dropped down into the receiving slot. Without a second thought, Amy opened the top and began chugging.
It was perfect. The soda was sweet. Almost too sweet. Tasting of berries and sugar and something almost vilely saccharine. Yet it quenched her thirst perfectly and within a minute, Amy was staring at the empty bottle, her desire for liquid sated. "Well, that was...uh, interesting" tail lightly flicking as she sat down to gather her wits.
Within moments though, her stomach began to gurgle violently. Pain shooting through her chest as she groaned, gasping for air as she clutched her arms to her torso. "W-What t-the h-hell!?" gasping out through the quite palpable agony that lasted for almost a minute before stopping.
When it was over, she looked around and down to a gasp of shock. The room seemed bigger. Her clothes certainly were really loose on her. And most importantly, her body was changing. Her legs were shortening a little, waist expanding just a touch. Her chest, nothing to laugh at a few minutes earlier was deflating like a balloon. When the feelings had stopped she looked at herself, stepping out of too big pants and oversized shoes, shirt not yet tent-like but still large on her. She had shrunk, a lot, finding herself barely over 4'9 now with only the faintest swell of a chest and, as she looked at her torso, a lack of a belly button.
But her tail was the same. Bigger now. Or at least it looked it. It didn't shrink, at least not as much as the rest of her body. As she watched though, she could see the light blue color beginning to spread, a wave of surprisingly delightful pinpricks happening all over her skin, going from a nice normal human color to a light blue, the same color as her tail.
The feelings, the absurdity of it, caused her to giggle. A musical sound, innocent on the surface with a deep undercurrent of mischief and malice. "This is awesome!" grinning bright and broad. Eyes scanning, the changing imp fixed her gaze on a....