There was a series of mysterious deaths when the victims were broken without any noticeable cause. Once the situation is exacerbated, and the 36th computer class Homura Kei is killed. Because of the criminal behavior of Kay, skipping class, it turns out to be surviving soul massacre. When he returns home that night, the hacker named Jouon arrives to his door. He argues that he also lost someone because of the mysterious killer, and he has information that Kay is not. Apparently, someone created a program that can affect people through the image of the blue butterfly on the computer screen, and that someone uses the program to kill people. Kay and Jun must find a killer before someone decides to destroy them! [TETHYSDUST]