Koji Tonoh (戸尾 耕司 Tonoo Kōji) is a university student and Omi Takahata's boyfriend.
He is voiced by Yasunori Matsumoto (credited as Dajitoro Kataoka).
Koji Tonoh though an average person with no knowledge of the supernatural seemed physically fit enough to fight off the transformed Yoh with a pipe and kill her as well as fend off the crazed Fuminori. Also dispite being horrified by the situation he had discovered he had the will power and sense of justice to confront it in an attempt to stop it.
Koji is a young man with light brown, grayish hair and dark brown eyes. He wears a blazer with a brown button-up shirt underneath.