Ingrid, once human, now..... something more, was the victim of a mad scientist's experiments to make himself immortal many years ago. The scientist made his victim immortal but not in the way he had planned. Her skin turned to plastic and it looked like that was all he had accidentally accomplished. When he leaned in to examine the inert form before him, she struck and with her new plastic fangs bit into his neck and absorbed much of his life essence leaving him transformed in to plastic as well. The only difference is even though he was fully conscious in his plastic body he was truly immobile, helpless to do anything but stand there as the creature that was Ingrid left him. Weeks later when the police investigated the seemingly abandoned house they found a mannequin in the middle of the lab.
Ingrid, still a mannequin in appearance retained her intelligence and had an overwhelming need to sate an appetite for life energy that seems to have no limit. She spent most of the year hiding in plain sight as just another mannequin among the others in mall stores. She moved from town to town often to avoid unwanted attention, discreetly leaving her newly mannequin victims in her place as she moved to the next store.
Halloween was her favorite time of the year. It was the one day of the year she could pretend to be normal again because her shiny, plastic skin wouldn't draw any attention to her with so many others dressing up for the holiday. She would dress up in what ever an outfit was popular and openly move about, going from costume party to costume party draining as many people of their life essence.
The Mighty Spectra also enjoyed Halloween for many of the same reason. She could patrol the city and stop in and enjoy the different parties going on across town and no one would make a big deal of her being there. Most people just assumed she was just wearing a Spectra costume and not think twice about it.
At one such party Spectra saw a couple of women off by themselves in the woods. There had been reports of strange happening going on in the area and she decided to see if she could talk them in to re-joining the rest of the party. As she drew near she didn't notice that the girl dressed as a demon was standing unnaturally still until the dark haired girl spun around supernaturally fast and bit deeply in to the now paralyzed Spectra's neck.
Ingrid pulled away from her newest victim and admired the view. She took a moment to pose her newest victims and wiped away the now plasticized blood from her lips. With the smile of a hungry predator she turned her back to the duo and with a sexy strut walked away looking for another party and more life essence.
Spectra and the other girl did the only thing they could do. Stand there and wait to be discovered in their immobile plastic bodies and revel in the euphoric sensations Ingrid's bite bestowed upon them.