Masae Atago is a professional mahjong player and a supporting character in the spin-off manga "Saki: Achiga-hen episode of side-A". She is the head coach of the mahjong club at Senriyama Girls' High School in North Osaka. Her daughters Hiroe and Kinue Atago attend Himematsu High School in South Osaka. 

The Achiga Girls' Academy in Nara once defeated regional mahjong powerhouse Bansei High School. It advanced into the national team semifinals but lost to the eventual champion, and the mahjong club was later disbanded. 
Six years later, elementary school student Shizuno Takakamo befriends transfer student Nodoka Haramura. The two eventually enter Achiga Girls', but Nodoka transfers out of the school in the second year. 
When Shizuno sees Nodoka on television the following year as the national middle school individual mahjong champion, she decides to revive Achiga's mahjong club.

The final 4 episodes of Saki: Achiga-hen - Episode of Side-A.

The Achiga Girls' Academy in Nara once defeated regional mahjong powerhouse Bansei High School. It advanced into the national team semifinals but lost to the eventual champion, and the mahjong club was later disbanded. Six years later, elementary school student Shizuno Takakamo befriends transfer student Nodoka Haramura. The two eventually enter Achiga Girls', but Nodoka transfers out of the school in the second year. When Shizuno sees Nodoka on television the following year as the national middle school individual mahjong champion, she decides to revive Achiga's mahjong club.

A Saki spin-off series. It follows the characters Toki Onjouji, Ryuuka Shimizudani and other girls from Osaka during their elementary and middle school years.

Side stories of the "Saki" manga in 4-koma format. 

Note: Chapter count includes 7 omake chapters, 1 from each Volume.

Special chapters of Saki Biyori serialized in Big Gangan.