81diver81 Diver; Hachi Wan Daiba; Hachi Wan Diver; Hachiwan Diver; Ныряльщик 81; ハチワンダイバー; 벌 원 다이버

Kentarou's former shogi teacher taught him to (metaphorically) dive into the 81 squares of the shogi board. Thus, his nickname is "81 Diver". He has failed to enter the professional league of shogi competition. However, he continues to play the game for a living by gambling at amateur shogi clubs.