https://www.cmoa.jp/title/318153/

The hometown of Miharu's missing mother was a beach village with a torii gate facing the sea. As the once-in-60-years grand festival to choose Ozan approaches, Miharu decides to go to the island of the shrine! (source: KManga, translated)

The story depicts the serious competition in the world of professional competitive mahjong between the "digital" school, which believes only in efficiency and probability, and the "occult" school, which believes in its own theories of unknown scientific basis, and the main character Natsuki, who belongs to neither of these groups.