Jess decided to choose the Naga vial, since she had always wanted to see what it was like to have a snake's tail instead of legs. She took the vial out of the box and uncorked it, sniffing it first and then she shrugged her shoulders as if to say 'what the heck' and dumped the liquid down her throat.
She waited a few seconds and then she began to feel the changes take effect. Her body was filled with pleasure as the vial began to change her body. She fell backwards onto the bed, letting the feelings wash over her. Her legs were the first to change, becoming much more flexible as her bones changed. Her legs then began to stretch, starting to join at her waist as she did so. She winced as this happened. She had forgotten to remove her jeans and she sighed with relief as they were ripped off by her fusing legs.
Her legs stretched to a length of almost 20 feet, and they finished fusing soon after. The thin legs began to get thicker as they were filled with the muscles that make a snake's tail so flexible. The skin at her feet began to crack and dry out, being covered over by small scales. Scales also started forming on her hands and waist.
The scales spread out from their starting points, covering her arms and her tail with black scales. The top of her tail was also covered with a dark green diamond pattern. Her hair fell out and the skin on the back of her neck spread and stretched to form a large Cobra hood on the back of her head. Her teeth began to grow pointed and venom pouches formed in her jaw. Her jaw also changed, becoming wider and giving her the snake's ability to unhinge her jaw.
Her fingernails moved to the center of her fingertips and hardened, turning black and growing into 2 inch long claws. The scales formed hard plates on her front, and her breasts expanded several cup sizes to a full and pert DD cup. The scales covered her breasts, but still left them smooth and soft. Her waist narrowed and her hips widened just a bit, giving her an attractive hourglass figure.
The final change occured as her face was covered in smooth soft scales and her eyes grew slightly, her irises turning golden and her pupils narrowing to slits.
Jess sighed, raising herself up from the bed on her tail. She looked down at her new tail, amazed at how long it was. She waited a few seconds, getting her balance, and then she began to slither her way towards the bathroom.
"Hey Mary, you still have that full length mirror in you bathroom right? I want to see how I look." She said, opening the door, being careful to not scratch it with her new claws.