This character plays shogi at some point in the story.
Shogi is a two-player strategy board game in the same family as Western (international) chess, chaturanga, makruk, shatranj and xiangqi, and is the most popular of a family of chess variants native to Japan.
Two players, Sente 先手 (Black; more literally, person with the first move) and Gote 後手 (White; person with the second move), play on a board composed of rectangles in a grid of 9 ranks (rows) by 9 files (columns). The board is nearly always rectangular. Each player has a set of 20 wedge-shaped pieces of slightly different sizes. Except for the kings, opposing pieces are undifferentiated by marking or color.