More or less the default protagonist of the game, Filia was once an Ordinary High School Student, but one day woke up without any memories and a second mouth on the back of her head. Now, she hosts a Parasite named Samson, an unruly mop of demonic hair with incredible power. With no memories or anyone to turn to for help, if she ever hopes to piece together her past and survive the inevitable clash with the Skullgirl, Filia will need to trust this mysterious being.