Takumi is a hikikomori and only attends school in order to fulfill the minimum for graduation requirements. He often and repeatedly notes that he is not interested in girls in the three-dimensional world and avoids conversations with others whenever possible. He prefers to engage in watching anime, playing eroge, and massively multiplayer online role-playing games. He is a second-year student at Suimei Academy.

Spoiler

Out of egoism to not get killed he starts to investigate the so-called The New Generation Madness cases. Later in the story, he realizes that all he had lived for was fake and only happened in order for him to awaken his abilities. His catchphrase is: Whose eyes are those eyes.

Spoiler

Eventually, Taku awakens his gigalomaniac powers and uses his DI-Sword to defeat Genichi Norose, the leader of N.O.Z.O.M.I., and destroys the Noah II artificial gigalomaniac device. This saves everyone from Norose’s diabolically evil plan of using the Noah II device to create a perfect utopia where everybody is happy and where the even more evil Committee of 300 will never be able to take power.