TV-Series
Description
Fujiwara no Sai is the ghost of a Go prodigy from the Heian period in Japan, a time spanning from 794 to 1185 AD. During his mortal life, he served as one of the Emperor's official Go instructors, a position of high prestige. However, he was wrongfully accused of cheating during a crucial match by a rival instructor who sought to eliminate him. Though the Emperor ordered the game to continue, the false accusation shattered Sai's composure, leading to his defeat. Disgraced and banished from the capital, he drowned himself in a river two days later, his soul becoming trapped within a Go board.

Centuries later, Sai was released from the board when it was found by a young man named Torajiro Kuwabara, who would later become known as the legendary player Honinbo Shusaku. Sai played Go through Torajiro, guiding him to become one of the most revered players in history. After Torajiro's death from cholera in 1862, Sai was sealed within the board once more, waiting over a hundred years until a boy named Hikaru Shindo discovered the board in his grandfather's shed. This time, only Hikaru could see or hear him.

In appearance, Sai is depicted as a tall, strikingly beautiful man with very long black hair that has purple undertones, typically tied with a white ribbon. He has purple eyes and purple lipstick, and wears the traditional court attire of the Heian era, including a tall black hat known as a tate-eboshi, a red-purple kimono, and a white haori over-robe. He carries a folding fan and wears red earrings. His delicate, effeminate features often lead others to mistake him for a woman, a characteristic that creator Yumi Hotta noted as appropriate for a high-born Heian man.

Sai's personality is marked by extreme emotional sensitivity and childlike enthusiasm. He experiences great mood swings, often crying copiously or becoming deeply moved by the beauty of a well-played stone. In his own time, such open displays of emotion were respected as signs of intelligence and sensitivity. When not engaged in serious competition, he can be cheerful, curious, and even humorous, showing wonder at modern inventions such as computers, which he refers to as boxes where people play Go, and expressing disbelief that humans have walked on the moon. However, when playing a match of significance, his demeanor transforms completely; he becomes focused, controlled, and intensely serious.

His motivations are singular and profound. Sai lives to play Go and to pursue the Divine Move, also known as the Hand of God, a perfect sequence of play that represents the ultimate expression of the game's beauty and depth. After being denied the chance to play for centuries, his greatest desire is to continue experiencing the clear, ringing sound of stones being placed on the board and to chase this unattainable ideal. He possesses a high sense of honor and abhors cheating or any act that defiles the purity of the game.

In the story, Sai serves as the mentor and guiding spirit for Hikaru Shindo. Initially, Hikaru simply executes the moves Sai dictates, allowing Sai to play through him. Over time, Sai teaches Hikaru the fundamentals of the game, though he is often a frustrated teacher when Hikaru fails to grasp concepts quickly. As Hikaru develops his own passion and skill, Sai gradually steps back, allowing Hikaru to play more on his own. Their relationship evolves from one of dependence to a deep, caring friendship, and Sai's eventual disappearance leaves Hikaru devastated.

Key relationships define his existence. He holds great respect for Koyo Toya, the reigning Meijin, recognizing in him a fellow seeker of the Divine Move. Their rivalry culminates in a legendary internet match where Sai triumphs by the narrowest margin of half a point, a game that fulfills a deep wish for Sai. His relationship with his former host, Honinbo Shusaku, whom he calls by his childhood name Torajiro, is one of mutual benefit and respect, as Shusaku willingly allowed Sai to play through him.

Sai's development throughout the narrative is subtle but significant. He begins as a ghost desperate to play again, frustrated that his new host is a boy with no interest in Go. As Hikaru grows, Sai comes to realize that his thousand-year journey was not simply to play more games but to nurture a talent that might one day surpass him and reach the Divine Move he could not achieve himself. After witnessing Hikaru's maturity and unique insight into a game Sai himself had just played, Sai understands that his purpose is fulfilled. He vanishes shortly after, not from despair, but from a sense of completion, leaving his legacy embedded in the way Hikaru plays the game.

His abilities as a Go player are extraordinary. Having played for over a thousand years and having learned from multiple eras of the game, he is considered one of the strongest players in history. His style is old-fashioned, rooted in the classical play of the Heian and Honinbo Shusaku eras, but he incorporates modern joseki and strategies after learning from Hikaru's era. His most notable talent is his ability to read ahead many moves into the future with exceptional accuracy, a skill that far exceeds normal professional standards. He is said to be one of the closest individuals to ever approach the elusive Hand of God.