Mary was about to drink when she decided to take off her clothes, to make room for any transformations. Once she was naked, she drank the entire glass in one swing.
Mary's entire body was tingling. She walked upstairs to her bedroom in what was like a drunken stupor. When she arrived at the foot of her bed, she fell down onto her back.
A sharp jolt of pain went through her backside after this action. She immediately rose off of the bed and felt at her ass. Where there would normally be nothing, she felt a long, furry appendage. She fell back onto the bed with shock.
She had a tail. "Only animals have tails" She thought. She realized that it was probably from the stuff that was in the vials. She got up, prepared to do something...