|School:||Kazekoshi Girls' High School|
|Debut:||Saki, Round 16 (unnamed)|
Akino Oosako is a member of the Kazekoshi mahjong team, however she is not a regular member. Akino shares all of her appearances with Masumi Asai, suggesting that they may be best friends.
Akino has medium length black hair and brown eyes. She wears the standard Kazekoshi Girls' uniform.
Prefectural Tournament Arc
She first appears after Mihoko's match and was one of the people responsible for collecting data on Tsuruga and Kiyosumi saying that she just wanted to be useful. She is then seen during Kana's match getting excited in anticipation of Kana Ikeda's big hand.
Individual Tournament Arc *anime only*
At lunch break on the first day Mihoko Fukuji charts her teammates success and says that Oosako might just barely be ok but needs to do better. She did not advance to the second day. She makes her last appearance cleaning the club room when Kana wonders where Mihoko is.