The visual novel was released on April 2008, and has already been adapted into a manga that started in May in ASCII Media Works’ Dengeli Daioh, and a second manga adaptation, a side story of Chaos;Head has already been announced, and will be serialized in Comic Alive.

The psychological thriller revolves around a high school student named Takumi Nishijo who witnesses a ghastly murder on his way home from school. As the mysterious murders starts occurring frequently in his home town, Takumi minds crumble into paranoia with the delusion that he could be the next victim.