"What....what's happening now?!??" Maria cried out.
Golden fur appeared all over her body, and her face felt weird. It suddenly extended into an odd muzzle shape. Her nose was black, and her tongue lolled out the side of her new mouth. Sharp teeth fell into place, Maria growled in discomfort. Two triangular ears appeared at the top of Maria's head, and her breasts bounced as they grew from B cups to DD. There were more of them as well, she had grown two additional pairs. They appeared more animal than human, the nipples dark and too long.
"Oh god, something is happening in my....." Maria doubled over, and Erica gasped when she saw her sister had a tail growing from her back.
"Oh crap, I shouldn't have picked up that bottle." Erica thought. She watched helplessly as her sister continued to transform into some canine like creature.
"Why does it feel like this?" Maria asked in the midst of her transformation. Her cock was erect, and going through a transformation as well. It grew from 5 inches to a large 10 inch red pecker. Her balls filled and doubled in size. Covered in a thin layer of fur, Maria stared in horror at her new canine penis and testicles. Still very much erect, Maria wasn't about to jack it off in front of her sister. Her arousal was being killed by the growing anger she felt toward her sister and that stupid bottle that did this to her. As the transformation slowed and ended, Maria stood up straight and snarled at her sister.
"YOU-DID-THIS!" she growled angrily.