Ginger Fitzgerald is the titular main antagonist as well as the protagonist of the horror trilogy "Ginger Snaps" and was originally a morbid girl who, alongside her sister Brigitte, loved to rebel against society's norms with violent and gruesome activities (most of which were staged and designed merely to shock the more "mainstream" people). She also has a loving but aggressive with Brigitte, which results in her becoming over protective of her.
However Ginger's life would change forever when one night she was attacked by what she believed was a rabid dog, in reality it was a werewolf and Ginger became infected with a virus that slowly mutated her into a werewolf herself - Ginger became more savage, animalistic and sexually active as the virus took over her body and began to develop more wolf-like traits such as a tail, ears and excessive body hair.
Ginger also started to become insane and infected others with the virus (which could be spread via sex or a wound) - she also became outright murderous and all the while her sister watched and became stuck in a nightmarish scenario where she had to come to terms with the fact that she would have to kill Ginger if she was to prevent a massive outbreak of the werewolf virus.
In the end of the film Ginger is transformed fully into a werewolf and attacks Brigitte, who manages to calm the savage beast before stabbing her - killing Ginger but holding her in her arms as she mourned her death..She returns as a spirit in the second movie and would watch over her sister (who is now cursed with lycanthopy), as she struggles life alongside a girl named, Ghost. Ginger also takes a more heroic role in the prequel film which cronicles Ginger and Brigitte's past lives.