81diver

81diver (ハチワンダイバー) is a Japanese shogi-themed manga series written and illustrated by Yokusaru Shibata. It was serialized in Shueisha's seinen manga magazine Weekly Young Jump from September 2006 to July 2014, with its chapters collected in 35 tankōbon volumes.

An 11-episode television drama adaptation was broadcast on Fuji TV from May to July 2008. It starred Junpei Mizobata as Kentarō Sugata and Riisa Naka as Soyo Nakashizu. The title refers to the main character's shogi nickname, which comes from the words of his former teacher who once told him to dive into the 9 by 9 (81) squares of the shogi board.

Plot
Kentarō Sugata failed at entering the professional league of shogi board game competition. However, he continues to play the game for a living by gambling at amateur shogi clubs. His encounter and defeat by the shogi player named Soyo Nakashizu, known as "Akihabara's champion" (アキバの受け師), shocks him and, combined with his financial crisis, reinvigorates him to take shogi more seriously. He also finds out by chance that Soyo offers a part-time maid cosplay house cleaning service, another side of her which further intrigues him.

Characters

 * Kentarō Sugata (菅田 健太郎)
 * Kentarō devoted himself to shogi for 20 years, but gave up on becoming a professional player after failing to get promoted to 4th dan. He devotes himself to becoming a professional after getting defeated by Akihabara's champion. After entering the Shogi Coliseum, he becomes a member of the Monji Corps, led by Mojiyama alongside Soyo, Sumino, and Mikado.
 * Kentarō devoted himself to shogi for 20 years, but gave up on becoming a professional player after failing to get promoted to 4th dan. He devotes himself to becoming a professional after getting defeated by Akihabara's champion. After entering the Shogi Coliseum, he becomes a member of the Monji Corps, led by Mojiyama alongside Soyo, Sumino, and Mikado.


 * Soyo Nakashizu (中静そよ)
 * Soyo is a 19-year-old female shogi player, known as "Akihabara's champion". She works part-time as a maid at the Akihabara Maid Cleaning Club. Having the strongest shogi skills out of all the characters, she had a 36221 winning streak until being beaten by Tanio. Her family runs a shogi dojo, and she was trained from an early age by her father and brother, who failed to become professional shogi players.
 * Soyo is a 19-year-old female shogi player, known as "Akihabara's champion". She works part-time as a maid at the Akihabara Maid Cleaning Club. Having the strongest shogi skills out of all the characters, she had a 36221 winning streak until being beaten by Tanio. Her family runs a shogi dojo, and she was trained from an early age by her father and brother, who failed to become professional shogi players.


 * Nikogami (二こ神)
 * A homeless shogi player in his late 70's. His real name is Shintarō Jinno (神野神太郎); because his name has two characters for god (神), he is nicknamed Nikogami. Nikogami's goals are to catch river fish and to continue playing shogi. He is an old acquaintance of Soyo, and was chosen by her as the first player to make Sugata stronger.
 * A homeless shogi player in his late 70's. His real name is Shintarō Jinno (神野神太郎); because his name has two characters for god (神), he is nicknamed Nikogami. Nikogami's goals are to catch river fish and to continue playing shogi. He is an old acquaintance of Soyo, and was chosen by her as the first player to make Sugata stronger.


 * Jirō Monjiyama (文字山 ジロー)
 * A shogi player and a manga artist. He is writing a manga titled Naruzō-kun (なるぞうくん), and has also written Naruzō-kun's Introduction to Shogi (なるぞうの将棋入門) His shogi ability is unstable, but he was chosen by Soyo as the second player to make Sugata stronger.
 * A shogi player and a manga artist. He is writing a manga titled Naruzō-kun (なるぞうくん), and has also written Naruzō-kun's Introduction to Shogi (なるぞうの将棋入門) His shogi ability is unstable, but he was chosen by Soyo as the second player to make Sugata stronger.


 * Shito Kirino (斬野 シト)
 * A shogi player and a doll maker who uses "Kirino resin" to make realistic dolls. He was chosen by Soyo as the third player to make Sugata stronger. He is gay and passionate about Sumino.
 * A shogi player and a doll maker who uses "Kirino resin" to make realistic dolls. He was chosen by Soyo as the third player to make Sugata stronger. He is gay and passionate about Sumino.


 * Kuru Kirino (斬野 クル)
 * Shito's younger sister. She is not very good at shogi and is currently studying.


 * Kuma Sumino (澄野 久摩)
 * Kirino's shogi master. He prefers power shogi, using the Primitive Central Rook opening, and does not mind which the hand played with. He spends his days fighting, and can win alone against several thugs.


 * Chiko Chidori (千鳥 チコ)
 * A legendary former female shogi player in her 40's. She began playing shogi when she was 10 and became a master at 12, inspiring Mojiyama, who was 6 at the time, to begin playing shogi. Chidori is credited with saving shogi, which was declining in popularity. Taught by Tanio, she fell in love with him, causing him to abandon her. Despite becoming the youngest female master, she suddenly retired, disappearing for 30 years. She used to work as a club hostess.

Manga
Written and illustrated by Yokusaru Shibata, 81diver was serialized in Shueisha's seinen manga magazine Weekly Young Jump from September 7, 2006, to July 17, 2014. Shueisha collected its chapters in 35 tankōbon volumes, released from December 19, 2006, to August 20, 2014.

Drama
An 11-episode television drama adaptation was broadcast on Fuji TV from May 3 to July 19, 2008.

Reception
81diver ranked first on Takarajimasha's Kono Manga ga Sugoi! 2008 ranking of best manga series for male readers. The manga was one of the Jury Recommended Works at the 11th Japan Media Arts Festival's Manga Division/Story Manga in 2007. It was nominated for the 12th Tezuka Osamu Cultural Prize in 2008.