Jess saw the drawer marked "Age," and a sly smile came to her face. She had always joked with Mary about she being Jess' "older sister," because the two friends were so close, yet Mary was only one day older than her. She thought it would be fun to turn the tables, albeit to an extreme degree. She opened the drawer and looked over the vials inside. They were each labeled with an age, from one month to one hundred years. Mary picked out "Age 10" and covered the label with her hand.
"No peeking," she said coyly as she handed it to her friend. Mary grasped the vial in her claw and opened it up. "This one isn't an animal, so don't worry. But I think you'll have to drink it all for the right effect."
"All right," Mary said hesitantly. She trusted Jess enough to believe that nothing bad was going to happen to her. At any rate, she could reverse the change easily, whatever it was. She downed the liquid in one gulp. Oddly, it didn't taste like anything but water.
Slowly, she noticed her shirt becoming even larger than it already was. "Did you give me the shrinking vial?" she asked, curious why Jess would pick that instead of an animal.
"Not exactly," Jess teased. "You'll figure it out."
Mary felt something in her chest, as if some pressure was being released from it. She looked under her very wide collar to discover that her breasts were shrinking. "What are you doing to me?" she asked, a hint of panic in her voice. There was also something else about her voice...was it higher than it used to be?
Mary saw her fingers shorten a bit as her hands lost their distinctly feminine appeal. Her midsection changed as well; her hips thinned and her waist lost its hourglass curve. Her panties slipped off, falling to her feet. When she looked back at her breasts, they had completely merged into her chest, leaving only six small nipples on the flat, furry surface. Her hands had become tiny and slightly chubby, as had her feet. "Am...am I getting younger?" she asked in a voice that sounded as if it was going through puberty.
Jess watched her "older" friend shrinking before her eyes. Mary's head was slightly disproportionate to her body, as a normal child's would be. Her eyes gained a youthful brightness. Mary's shirt came all the way to her ankles, its collar so wide it fell over one of her furred shoulders. She was barely over two feet tall now. Her cute little hands poked out of the massive sleeves as Mary surveyed her final changes.
"Youwww made me a kid!" she whined in a high-pitched voice. A few mews escaped her mouth as she made the accusation. "Why'd yowwww do that?"
"Because you're even cuter this way!" Jess smiled.
Mary glanced at the empty vial in her hand, reading the label. It took her slightly longer to recognize the letters than usual. "Age...ten? But...but I wanna be grown up!" Tears began to well in her eyes.
"There there," Jess knelt down and patted her head. She couldn't believe she had actually changed her friend, the excited and attractive cat-woman, into a whiny little cat-girl. "If you want, I can give you another age vial. I only wanted to play a little joke."
Mary sniffed back more tears. "Yes! Change meow back to normal!" She started pounding Jess with her weak paws.
Jess didn't expect the vial to change her age mentally as well. She went back to the vial box to get her something else.