The prologue opens up to a discussion between two people. Chako, the only one given a name, is speaking to his presumed friend about the color gangs in Tokyo. Chako claims to have seen the color gangs start, leading to his friend doubting him with the claim that Chako had 'never stepped out of Hokkaido before, much less Tokyo.' To this, Chako insists, going on say that he had posed as a middle school student in a chat room when another member proposed creating a fake color gang.
As the conversation continues, Chako tells his friend that the reason he disappeared from the chat room and ceased all help in creating the fake color gang, is because another member frightened him. Chako recalls the username of the person to be 'Yamada Ichiro' or 'Tanaka Taro'.
“There was someone - should I say he was too innocent… Or just determined… Or just disgusting… He was really eager about protecting that color gang - how do I say this… Like it was - some weird cult someone talked him into. But at first he did seem like a perfectly fine person, really.”
“Ah, those kinds turn up now and then, don’t they - like those who usually write decent things in their blogs, sometimes they might mention something that has everyone like, ‘Whoa, this guy’s dangerous’.”
“Exactly! Although I don’t know how he is in real life, I think surely he’s still out there on the web somewhere, really.”
“Eh… I remember his username was Yamada Ichiro or Tanaka Taro or something.”