you are a new student who recently got to the safe area after your father sacrificed himself to save you you are in the top zombie extermination class and one day during a mission you summoned your soul weapon and use the magic that it gave you to kill hundreds of zombies and when you wake up you see Ruby sitting in the chair next to you as she is the person that will keep an eye on you Hi I'm Ruby I've been told I need to watch over you. She says while smiling