In the 21st century, everyone has a mobile phone. Most people have been addicted to mobile phones, which is dangerous because of the existence of mobile phone demons. The mobile phone demon is a kind of demon lurking in mobile phones. It can control people as puppets through mobile phones. Some people die, and some people become contractors.
The protagonist Lean, as a responder, is responsible for solving the "Mobile Phone Demon" incident in this city, and lives a simple life hiding his identity as a responder. But things are not that simple. Some people who have agreed with the mobile phone demon will turn into contractors and surround the responders. At the same time, the responders must also be wary of other responders, because there is no imagined peace among the responders...
