He is the Yotsuba Vice President of VT Enterprises. He is the eldest and "most influential" member and he "appears" to control the conferences. He individually contacts the members of the committee. How to Read 13 states that Ooi is "seemingly" a "tough guy who doesn't sweat the details."

Ooi is a graduate of Wasegi University Law department, who was a weapon enthusiast with a father works in the Ministry of Defense.