Jess was looking at all of the mythical vials when one caught her eye. It was a picture of Cerberus, the three headed guard dog of the underworld.
Her breath quickened slightly. She had always fantasized about being a cerberus. She had put that dream away some time ago because it was a crazy dream, but now it was starting to look more and more real.
She took the vial out of the case and opened it, putting just a little bit in her mouth at first, to test the taste, then she dumped the whole thing down her throat before she could start to doubt her decision.
Mary hadn't seen the label, so she was surprised when Jess drank the whole thing. "I hope you know what you're doing." She said.
Jess sighed, the beginnings of a change washing over her. She felt herself becoming more horny and she started to wet her panties. "Trust me, I want this." She said, lightly rubbing her left breast.
She fell back onto the bed as her skin started to darken, settling into a very deep black color. Then, short, but thick fur began to grow all over her body, leaving a small grayish patch on her stomach and breasts, ending at a triangular point near her vagina.
She moaned as the changes began to pick up speed. Her fingernails thickened and changed to claws, while her hands stayed thin and delicate. The same thing happened to her feet, which was announced by the loud ripping of her shoes. Her feet began to change to a digigrade structure, her feet extending and her toes getting a little bigger to allow her to walk.
Her arrousal had increased even more and she easily shredded her shirt and pants with her free hand, the other still massaging her breast.
Now clad in only a bra and a pair of dripping wet panties, the changes began to define themselves. Her eyes changed to a dark, blood-red color, and her canines lengthened into sharp fangs. Her nose broadened out and turned black, as her face began to push out into a muzzle.
Her ears turned black and pointed and they moved up to the top of her head. She couldn't take it anymore, and she ripped off her bra and panties, violently rubbing her breasts with one hand, while she began to forcefully rub her crotch with the other hand.
Her breasts, seemingly unchanged by now except for color, quickly caught up with her. The grew and firmed up, stopping at very pert, gravity-defying EE cups. A black tail grew out of her back just above her now perfect ass, stopping at a length of about 3 feet. It was covered in the same fur as the rest of her.
Mary seemed to think that the changes were complete, Jess had picked a werewolf vial. She opened her mouth to say something, but she noticed that something else was happening to Jess.
Two large bumps began moving around under her skin on both sides of her neck. These bumps grew and gained definition, quickly growing to form two more heads identical to Jess' own head.
She stood up from the bed on her new feet, the digigrade stance making her an extra 6 inches taller. She let out a chorus of howls from her three heads and her body began to grow, putting on more muscle. The new muscle made her much, much stronger, but it did not alter her nearly perfect feminine form. If anything, it seemed to increase her curves.
The finishing touch was put on as two rows of small teats formed on her chest, growing into two more sets of breasts that were slightly smaller than her original pair. She grew a little taller for her body to be better proportioned and then the change was complete.
Mary was a little nervous. She didn't know if the vial had altered Jess' mind with the change. She backed up a little, but froze instantly when 3 pairs of blood-red eyes locked onto hers.
"J..J..Jess...Is that you? Oh god Jess...please let that still be you. Don't try to hurt me..."
"Don't worry Mary. It's still me." The middle head responded, giving her a smile that revealed her sharp teeth. She looked herself over, going to the full length mirror in Mary's bathroom.
"Oh god..." She said, looking at the new her. She did a few poses and unconsciously played with her new breasts as she admired her new form.
"This is incredible. It's just like I dreamed." Jess whispered to herself. "God I love this." She said, closing her eyes and reveling in the sensual bliss.
She then realised that she now had three heads, so she tried to let her mind spread out through all of them. She then opened her eyes and her head swam for a few seconds before her brain adjusted to handling the input from three different heads. She spoke, seeing if she sounded any different from the other heads.
"I'm so beautiful." "I love this." "I'm staying like this forever."
She smiled, her voice was the same from all three, but she seemed to have aquired a very sext tone to her voice. Her ears twitched as she heard Mary enter the bathroom. "Oh god, Mary. Thank you for letting me use the vials. I love this!" Jess said, walking over to where Mary stood. Her hips seemed to sway sexily as she walked, and her nipples caught the cool breeze blowing from the air conditioner and quickly became erect.
She was finding it hard to control her arrousal, but she knew that it was not all from the transformation. She had secretly been this way all her life, she had just been too shy to express her true feelings.
She sat down on the bed and slowly rubbed her moistening crotch.
"Okay Mary. It's your turn. You have to try one of the mythical vials too. Trust me, they're definately worth it."
She continued to gently rub herself as Mary came out of the bathroom.
Mary was excited. If shy Jess was that happy with her choice, she would probably enjoy it too.
"Okay, just a second though. I want to make sure I get the most out of this." She picked up the human female vial and drank the whole thing, reverting to her normal appearence that she had had before she got the vials. She put the vial back, and then began to look through all of the mythical options.
She finally decided to choose...