Minami Senju, Chimari Maiko, and Nao Mejiro venture inside the light novel Shogi King's Big Job!, coming up against turtle viruses that can only be defeated by clearing tsume shogi problems. Aided by the novel's heroine, Mai Tsurumizu, the girls learn that Maya has captured her master, along with other strong shogi players, and trapped them inside the shogi hall. Helping the girls get past all the shogi problems, Mai soon faces up against the Mother Virus in a shogi battle while Maya dispatches viruses to try and distract her. Despite drawing close to her limit, Mai manages to give and receive encouragement from Chimari, allowing her to beat the Mother Virus.