Hiroko Funakubo is a second-year student at Senriyama Girls' High School in North Osaka and a supporting character in the spin-off manga "Saki: Achiga-hen episode of side-A". She is the strategist of the Senriyama team and carefully researches the performance and skills of opposing players prior to tournaments. She is a cousin of Hiroe and Kinue Atago of Himematsu High School in South Osaka. She is also a niece of Senriyama mahjong club supervisor which weighs a lot on her because people outside the team think that she got her position because of relations and not skill.