Tougo Narutaki has a brief moment in the early episodes of the first season. He is shown as Tatsuma Hiyuu's martial arts master, and also the person who enrolled Tatsuma in Magami Academy, telling the boy his talents would be needed. Afterwards, he seems to disappear.
Tougo emerges in the anime's second season as the Chief of the assassin organization, Martial Fist. He has also taught Kureha Mibu his martial arts. Dark and professional, Tougo surprisingly is an antagonist and supposedly the one who orders the hit on the Magami Five. However, the dismal character is renounced as a familiar-spirit sent by Munetaka Yagyuu to use the Martial Fist, and the real Tougo returns to once more take command of the organization and help the new Stars of Fate.
The character is debuted in the videogame "Tokyo Majin Gakuen Oboro-Kitan" as a close friend of Genma Hiyuu (Tatsuma's biological father) which is also shown throughout the anime in flashbacks. Together Genma and Tougo created their martial arts form Yin no Toshukuuken.