Protagonist who is assisted by Sai. At the beginning of the series, Hikaru is a sixth grader in elementary school. An important factor in the development of Hikaru's passion for Go was an encounter early on where Hikaru becomes the rival of Akira Toya. At first, he thinks that Go is just for oldsters and he is annoyed at Sai's demand to play, but little by little his passion for Go increases as he plays more and more. From being a member of a school Go club to being an insei and finally becoming a professional Go player (at 14 years old) a year after Akira, Hikaru matures throughout the course of the series. Throughout the series, Hikaru gradually gets taller because the manga volumes are around when he is getting older and playing Go at the same time. Hikaru is often portrayed wearing clothing having the numeral "5". This is a pun on the Japanese common name for five: go. His birthday is September 20th. Part of his strength is his ability to read far into the game very fast, and to make seemingly stupid moves. These moves in fact lure the opponent to doing stupid moves, which Hikaru then traps them by.