Takao Hiyama

Takao Hayama was teacher turned serial killer in the city of Sakaurami, Japan before he was approached by a mysterious entity named Deus Ex Machina, claiming to be the "God of Space and Time", and placed in a battle to become a god, the successor of the current god, who was dying. Deus gives Hayama a "future diary", a modified cell phone given to him by Deus which can predict his certain aspects of his future, in Hayama's case, how his victim will try to escape, but says nothing on how they will fight back. Like all "diary holders", if the diary is destroyed, Hayama. Hayama used a large Bowie-style hunting knife for his kills. Hayama wears a a bullet and blast resistant jacket that provides protection from small caliber rounds and some protection from explosive blasts, as seen in his fight with Minene Uryuu. Uryuu escapes by disabling Hayama with a flashbang, and is later killed by Yukituru Amano, who hits him with a thrown dart to his "future diary".