The Ryuo's Work Is Never Done!

*The Ryuo’s Work is Never Done!* is a story about a teenage boy named Yaichi Kuzuryu who happens to be the strongest shogi player in history, holding the top title of “Ryuo”(Dragon King).
One fateful day, shogi-loving elementary student, Ai Hinatsuru, appears before him claiming that he promised to be her master. But was such a promise really ever made? Thus began their master and disciple relationship! 

(Source: Bookwalker Global)