Producer Koji Nagai was born in Kobe, Japan. Since 1993, he has directed music programs, informational programs, and variety shows, among others. 

He has been an animation programs producer since 2006, and has produced shows such as Ace Attorney, Space Brothers, Space Brothers #0, MIX meisei story, Magic Kaito 1412, The Kindaichi Case Files R, Kekkaishi, Yashahime: Princess Half Demon, Firefighter Daigo: Rescuer in Orange, Case Closed, and My Hero Academia.

He is currently a director and the Tokyo Business Development Division Headquarter, in charge of not only anime, but also music and anime merchandising.

He enjoys many hobbies such as music activities, car racing, scuba diving, travel, and photography.