Hikaru Shindou

Hikaru is energetic, impulsive and highly competitive. At the beginning, he has little patience for Go's traditions and frequently argues with Sai about being forced to sit through games he does not understand.

His attitude changes once Go becomes connected to people his own age. Akira's intensity makes Hikaru want to understand why the game matters so much, while school tournaments, Go salons and friendships with other players give him goals independent of Sai.

Hikaru hates being treated as though his achievements belong to someone else. This becomes increasingly important as he develops: he wants opponents to recognize his own Go rather than the supernatural strength they once saw when Sai controlled his moves.

Hikaru develops unusually quickly from a complete beginner into a serious Go player. His early exposure to Sai gives him access to elite-level analysis, but Sai does not simply transfer his ability; Hikaru must learn joseki, reading, shape, positional judgment and competitive discipline himself.

One of Hikaru's strengths is his ability to read sequences quickly and find moves that initially appear strange but create deeper tactical possibilities. His style becomes increasingly aggressive and inventive as he gains experience.

He also learns effectively by replaying games. Sai's constant presence gives him an exceptional teacher, while competition against players such as Akira, Yoshitaka Waya and Shinichirou Isumi forces him to develop independently.

Hikaru discovers Sai while searching through his grandfather's possessions and reluctantly agrees to place stones for him. Sai's victory over Akira creates an immediate problem: Akira becomes convinced that Hikaru himself possesses extraordinary strength.

Wanting to play Akira with his own ability becomes one of Hikaru's first major goals. He joins school Go activities, enters the insei system and begins competing against young players aiming for professional status.

Hikaru passes the professional exam at fourteen and becomes a 1-dan professional. After Sai disappears, grief causes him to stop playing temporarily, but a game with Isumi makes him recognize traces of Sai within his own Go and gives him a reason to continue.

Hikaru later represents Japan at the Hokuto Cup and insists on taking first board against Yeong-ha Ko. He loses their exceptionally close game by half a point, but the match reinforces his belief that Go connects players across generations—from the distant past through the present and into the future.

Fujiwara no Sai is Hikaru's supernatural companion and first Go teacher. Fujiwara no Sai initially plays through Hikaru, then guides him as Hikaru develops his own ability.

Akira Touya is Hikaru's central rival. Akira Touya spends much of the story trying to understand the impossible strength Hikaru displayed in their first games, while Hikaru works to become strong enough to face him without Sai.

Akari Fujisaki is Hikaru's childhood friend and becomes interested in Go partly through him.

Yoshitaka Waya becomes one of Hikaru's closest friends within the insei system and a fellow professional prospect.

Shinichirou Isumi is an older insei whom Hikaru respects. A later game with Shinichirou Isumi helps Hikaru return to Go after Sai's disappearance.

Kouyou Touya takes an unusual interest in Hikaru because of the extraordinary games associated with him and his rivalry with Akira.