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."
He works with the Yotsuba Group, but later dies of a heart attack with the other members, the result of Light writing their names in the Death Note.
Ooi is a graduate of Wasegi University Law department, who was a weapon enthusiast with a father works in the Ministry of Defense.