Future Diary is a Japanese manga series created by Sakae Esuno. It follows a high school student named Yukiteru Amano, who receives a diary that can predict the future. This diary allows him to foresee events before they happen, putting him in a deadly survival game against other diary holders. The game, orchestrated by Deus Ex Machina, the god of time and space, involves 12 participants who must eliminate each other to become the new god. As Yukiteru navigates this dangerous competition, he forms complex relationships, particularly with Yuno Gasai, a fellow participant with a deep obsession for him.