3-gatsu no raion zenpen

17-year-old Kiriyama Rei is a promising professional shogi player. His family died in an accident when he was young, and he was adopted by his father's friend Koda, a professional shogi player, and started to be trained to play shogi with his foster brother and sister. He had to leave his foster family after conflicts with them, trying to live independently without family, friends or anyone care about him. Things started to change when he met the Kawamoto sisters, a family who decided to take care of him and protect him as one of their own. Meanwhile, Rei becomes acquaintances to many different kinds of professional shogi players as he plays with them, and his bond with those players starts to change his attitude toward shogi.