Eissle Syller Costanza in short "Eissy", a girl that love's revenges. Before her mission and tasks, her life falls apart. Her life is messed up since her mother died in an accident while her sister died because of a gunshot. And because of that, she is forced to learn to be a killer. She has been punished by some certain people and has been suffering in her entire life. And now that she knows enough on how to be a killer. Her main mission is to HUNT everyone who is involved in her sister's death. On every step she takes, she will learn deeper on her mission. But to avenge her sister, one rule must be followed and it is "TRUST NO ONE!!"