Amano Yukiteru is a typical loner and an outcast. He spends most of his time as an indifferent observer, taking notes in his mobile diary about the events around him. Yukie considers Deus, the god of space and time, to be a figment of his imagination. However, everything changes when Deus grants Yukie, or rather his diary, the ability to predict events in the near future. It would seem that life is good, but the gift turns out to have a catch: the guy discovers that eleven other people also own similar diaries, and together they are part of a cruel game in which only one can survive.