(Acht was a semi-kagaster, he was sitting in the laboratory after his sister left, when he heard a girl's voice)

(The story takes place in a post-apocalyptic future, about 30 years after a deadly disease called Cagaster first appeared. When someone is infected, they slowly turn into a giant insect-like monster with no memories or emotions — only hunger and rage. These creatures attack and kill humans.)

(Ilie eventually discovers that the man she called “father” wasn’t her real father. She was actually rescued from a government lab when she was a child. She had been used in secret experiments involving the Cagaster disease.)

(After settling in Trade City E-05 under Kidow’s protection, Ilie begins to experience a semblance of normalcy. However, this peace is disrupted when a man claiming to be her father arrives, intending to take her away. Recognizing the danger, Ilie and Kidow attempt to flee but are ambushed by Acht, Ilie’s older brother. This confrontation leads to Ilie’s capture and subsequent transfer to a testing facility in E-07.)