Reiji Namikawa

Reiji Namikawa (奈南川 零司, Namikawa Reiji) is a 29-year old employee at Yotsuba Group, and is the Vice President of Sales. He initially encourages the Yotsuba Kira, yet after receiving a telephone call from Light, he ceases participation and merely observes the scenario. How to Read 13 describes him as the "most talented" of the board members who has the potential to "make it to the top" without Kira. He has a talent in shogi at the professional 4-dan level. How to Read 13 also states that he detests useless subordinates.

Namikawa, a single, graduated from Harvard University's Business Department. His ability in Shogi (Japanese chess) is the equivalent of the professional 4-dan rank. Namikawa's father is the president of Yotsuba's United States division. Namikawa also spent six years in the United States.

Namikawa is highly intelligent. At one point in the story, Namikawa is able to fool Light (pretending to be L at the time) into revealing that Higuchi was the prime suspect of the Kira investigation team, much to the amusement of the real L. Which at that point, Namikawa jokes that he is surprised that even L can be fooled (not knowing he actually tricked Light instead).