The Ryuo's Work is Never Done!: Charlotte Izoard, Ayano Sadatou, Mio Mizukoshi, Ai Hinatsuru

The Ryuo's Work is Never Done! is an anime about a teenage boy named Yaichi Kuzuryuu is the strongest shogi player in history (kind of like chess), holding the top title of Ryuo. One fateful day, a shogi-loving elementary student, Ai Hinatsuru, appears before him claiming that he promised to be her master. However, Yaichi couldn't recalled about the promise with a girl in the final match when he get the title. Playing along with her request, Yaichi asked her to pass first his test before accepting her as a disciple. At first, Yaichi doubted her ability. However after they did a trial match, he found out that Ai has a hidden talent to play shogi.