Mako Someya is a second year student and member of the Kiyosumi Mahjong Club, being the first member to join under Takei Hisa's leadership. Her family runs a mahjong cafe, which was former mahjong parlor. Being surrounded by Mahjong ever since she was young, Mako is familiar with many scenarios during the course of a game and is able to recall them during gameplay when taking off her glasses.