Seiji Ogata

Ogata is ambitious, observant and intensely competitive. He belongs to a generation that has spent years beneath dominant title holders such as Kouyou and Kuwabara, and he is eager to establish himself at the top.

He becomes fixated on information that does not fit. Hikaru's occasional insight far exceeds his apparent level, while the anonymous sai appears online with the strength of a world-class player but no identifiable professional background. Ogata refuses to dismiss either mystery.

Outside formal matches, he can be pushy and intimidating when pursuing an answer. His relentless questioning of Hikaru reflects the same temperament he brings to Go: once he sees a promising line, he keeps following it.

Ogata is one of Japan's strongest younger professionals. His 9-dan rank and repeated appearances in title competition place him among the elite players immediately below or alongside the established champions.

His Go is analytical and aggressive. He studies opponents closely and searches for weaknesses, but his tendency to think deeply about hidden possibilities can sometimes become a liability when an opponent deliberately gives him too much to consider.

Ogata eventually captures the Judan title from Kouyou and later adds the Gosei title, establishing himself as a multiple-title holder. He continues challenging Kuwabara for the Honinbou title as part of his effort to supplant the older generation.

Ogata notices Hikaru at a children's tournament when the boy explains the significance of a move that professionals themselves need time to appreciate. The insight actually comes from Sai, but Ogata has no way of knowing that.

He later helps Hikaru enter the insei examination process and follows his progress. When sai becomes famous through Internet Go, Ogata becomes increasingly suspicious that Hikaru has some connection to the mysterious player.

After Sai's Internet match against Kouyou, Ogata questions Hikaru aggressively about sai's identity. Sai later gets his wish to play Ogata when a drunken Ogata plays Hikaru; Hikaru secretly allows Sai to direct the game, leaving Ogata unaware of who is actually sitting across from him.

Kouyou Touya is Ogata's teacher and one of the professionals he most respects. Ogata eventually defeats Kouyou Touya for the Judan title.

Hikaru Shindou attracts Ogata's attention through insights that seem impossible for his experience level. Ogata later suspects that Hikaru Shindou knows the identity of sai.

Akira Touya is the son of Ogata's teacher and another young player whose development Ogata observes closely.

Kuwabara is one of Ogata's principal professional rivals, particularly over the Honinbou title.

Fujiwara no Sai becomes an opponent Ogata desperately wants to identify and face. Ogata eventually plays Fujiwara no Sai unknowingly when Sai directs Hikaru's moves during their game.