The Ryuo's Work is Never Done!

Yaichi Kuzuryū is a prodigy shogi player who won the title of Ryūō at the age of 16. Following his victory he has been in a slump, until he is approached by Ai Hinatsuru, a 9-year-old girl who begs him to make her his disciple. Astonished by Ai's potential, Yaichi agrees to become her master, and the two then brave themselves together in the world of shogi with their friends and rivals, but under a condition imposed by her mother that he is to marry her if she does not become a major player before graduating middle school.

Yaichi Kuzuryū (九頭竜 八一, Kuzuryū Yaichi)

Voiced by: Yuuma Uchida[1]

The main protagonist of the series. Yaichi is a sixteen-year-old who won the Ryūō title match at a young age. He is the current youngest Ryūō. Initially he was overwhelmed by his title and perceived pressure to avoid playing in a "disgraceful" manner. He has a calm personality and often doesn't take things seriously unless they are related to shogi. He was taken aback by Ai's talent and determination, and the way she continues to fight and seek a way to victory has helped inspire him. Yaichi is often wrongly accused of being a lolicon due to the affection he gains from young girls like Ai and her friends Mio, Ayano, and Charlotte in her shogi training group. Despite their affections for him, he is oblivious to their true feelings for him. Yaichi tries to be a good master to his disciples and does his best to teach the easiest steps so that his disciples can catch on quickly. He seems to have feelings for Keika as seen in some episodes of the anime.

Ginko Sora (空 銀子, Sora Ginko)

Voiced by: Hisako Kanemoto[1]

Yaichi's childhood friend and fellow disciple. Ginko is sharp-tongued, brash, and shows no mercy to her opponents in shogi. She is fourteen years old and considered the most talented girl in the shogi world, one of few with enough talent to potentially enter the main shogi league as a full-fledged professional rather than a professional in the women's league. Ginko currently holds an impressive undefeated record at 47 wins against female pros earning her the name "The Snow White of Naniwa". She became a disciple before Yaichi despite being two years younger than him. She never entered the women's league and continues to pursue the main Japan Shogi Association, and is implied to have done this to pursue Yaichi himself. Though not a female professional, she still holds the Queen title. Despite her aggressive attitude towards Yaichi, Ginko cares deeply about and has feelings for him, though she is hesitant to show it. In Volume 11, Yaichi confesses to Ginko and she reciprocates his feelings.

Ai Hinatsuru (雛鶴 あい, Hinatsuru Ai)

Voiced by: Rina Hidaka[1]

Yaichi's first disciple, a nine-year-old third grader. She is a cheerful girl with extreme talent for shogi, as well as the daughter of the owners of a large and popular inn which has been the site for major matches. She holds great admiration for Yaichi for his determination and refusal to give up after witnessing his Ryūō match. She first met an exhausted Yaichi during his previous Ryūō title match, where after rejuvenating him with a glass of water, Yaichi promised to grant her any wish if he won. Three months after the title match, she ran away from home to become Yaichi's disciple. Initially accepted as a temporary disciple over spring break, her parents tried to bring her home claiming concerns about the stability of life as a female professional. She failed their conditions to continue her discipleship, but Yaichi was sufficiently impressed by her determination and performance under great pressure. Afterwards he personally requests to take her on, even accepting the condition that, if she fails to claim a title before graduating junior high, he would marry her and inherit the inn. She is exceptionally possessive of Yaichi and occasionally demonstrates yandere traits. In shogi, her style places emphasis on the late game and is primarily "offensive", focused on finding ways to press the attack.

Ai Yashajin (夜叉神 天衣, Yashajin Ai)

Voiced by: Ayane Sakura[1]

Yaichi's second disciple, also nine years old and in the third grade. She has been living with her wealthy grandfather since her parents' deaths. Her father was a skilled amateur shogi player who'd met a younger Yaichi years ago while having an exhibition match against the Meijin. After Yaichi found a path that would have given him a checkmate, Ai's father had suggested that Yaichi someday take his daughter as a disciple, to which he agreed. She was frustrated to see that he does not remember her father, who'd never stopped admiring him, but eventually accepted his request to make her his disciple. She is very proud and prone to display tsundere traits. Her shogi style is opposite to Ai's, showing a deep understanding of the early game and a strong insight into "defensive" play, based on traps and counterattacks. The way her style complements Hinatsuru Ai's is part of the reason that Yaichi felt she'd make a great rival for her.

Keika Kiyotaki (清滝 桂香, Kiyotaki Keika)

Voiced by: Ai Kayano[1]

Yaichi and Ginko's elder disciple and biological daughter of their master. She entered the training association to attempt to become a female professional at the age of ten. At twenty-five, she is rapidly approaching the maximum age at which one can become a professional or female professional, a fact that is frequently demonstrated to cause a great deal of pressure for her. She is noted to be quite skilled when she relaxes, but still has a tendency to fall back into the standard basics and freeze up when opponents step out of common patterns. She seems to have an interest in Yaichi.

Mio Mizukoshi (水越 澪, Mizukoshi Mio)

Voiced by: Yurika Kubo[1]

A friend of Ai's from the training group.

Ayano Sadatō (貞任 綾乃, Sadatō Ayano)

Voiced by: Chinami Hashimoto[1]

A friend of Ai's from the training group.

Charlotte Izoard (シャルロット・イゾアール, Sharurotto Izoāru)

Voiced by: Yui Ogura[1]

A friend of Ai's from the training group, who is only six years old. A first grader attending a French school in Kyoto, she speaks with a childish, uneasy Japanese. Yaichi finds himself frequently overwhelmed by her cuteness, much to Ai's chagrin. She studies under the same master as Ayano. Not wanting to hurt Charlotte's feelings when he refused to switch and become her master, Yaichi offered to make her his "bride" instead. While this was successful in avoiding trauma from his rejection, her repeated mention of this "proposal" has caused some trouble for him. She seems to have an interest in Yaichi as seen in the anime.

Takashi Hinatsuru (雛鶴 隆, Hinatsuru Takashi)

Voiced by: Ichiro Mizuki[2]

Ai's father and Akina's husband. Having married into his wife's family, he is unable to contradict her.

Akina Hinatsuru (雛鶴 亜希奈, Hinatsuru Akina)

Voiced by: Mitsuko Horie[2]

Ai's mother and Takashi's wife, and proprietor of a prestigious inn. She attempts to prevent Ai from pursuing a shogi career claiming concern over the stability of such a life. When her daughter failed to satisfy her requirements she attempted to take her back home, but relented and accepted Yaichi's personal request to take her as a disciple under the condition that, should she fail to achieve at least one title before graduating junior high, Yaichi would marry into their family and inherit the inn.

The light novel ranked first in 2017 in Takarajimasha's annual light novel guide book Kono Light Novel ga Sugoi!, in the bunkobon category.[7] It ranked first again in 2018,[8] and second in 2019.[9]

Kei Mizutome (水留啓, Mizutome Kei) listed the book as one of four "essential" novels introducing shogi to a wider audience, saying that it was well-researched and that people familiar with the shogi world can guess on whom the characters of the Meijin and Maestro are based.[10]

• No-Rin, another light novel series by the same author

• Anime official website (in Japanese)
• The Ryuo's Work is Never Done! (light novel) at Anime News Network's encyclopedia