Kentaro's former shogi teacher taught him to (metaphorically) dive into the 81 squares of the shogi board. Thus, his nickname is "81diver." 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. (Source: MU)

81 Diver ranked first in the 2008 Kono Manga ga Sugoi! for the Male Readers division. The manga was adapted into a Japanese live-action drama series that aired from May 3, 2008, to July 19, 2008. It was also adapted into video games for the Nintendo Wii, Nintendo DS, and PlayStation 2.