Takao Hiyama

Background and Diary
Takao Hiyama is the homeroom teacher of Amano Yukiteru and Gasai Yuno. He is also a serial killer responsible for many murders at the beginning of the series. His diary is the "Murder Diary". This Diary gives him information about his victims such as their location and how he kills them.

Personality and Apperance
He wears a long bullet proof trench coat and a mask to hide his face. Both are a deep green. He has long red hair. He kills his victims with a knife. He is extremely paranoid, a characteristic that Murumuru guessed would lead him to be the first to be killed.

The Game Begins
Suspecting that Yukiteru is a diary holder due to his recent confidence he decides to kill him. He follows his diary's instructions and follows him and Yuno to a construction site. There he goes to the 14th floor and then the roof. On the roof unable to find his prey he checks his diary. When he pulls it out Yukiteru throws a dart at his diary and he dies.

Trivia

 * He is the first diary holder to die.
 * He is killed by Amano Yukiteru.
 * When he first gets his diary he destroys it out of paranoia as he thinks it might be used aganist him.