Second-year high schooler Amano Yukiteru is a boy who has problem making friends. He thinks of himself as a bystander and will always write down everything he sees in a cell phone diary.

Tormented by solitude, Yukiteru began to imagine things like a friend called Deus Ex Machina who is apparently the Lord of Time & Space. Seeing Yukiteru's miserable state, Deus gives him a new ability - his diary will now record events that will happen in the near future. Yukiteru is then forced to participate in a game which the winner will become Deus's successor.

Now a vicious game of survival is about to begin among twelve future diaryholders - with the winner crowned god of the new world!