Arata Sagimori is a secondyear high school student at Achiga Girls Academy in Nara Prefecture and a protagonist of the spinoff manga Saki: Achigahen episode of sideA. She is a childhood friend of Kuro and Yuu Matsumi her family owns a bowling alley in the area. As a kindergartener she grew up playing mahjong with adults at the Matsumi inn but stopped playing after her first year of elementary school. She is an admirer of Harue Akado and thus lost interest in the game after Harue stopped playing following Achigas loss in the national tournament. When Kuro informs her that Harue has begun playing mahjong again Arata agrees to join Achigas mahjong club. She was assigned on the position of Achiga mahjong club president by Harue as most levelheaded member of the team.