The Twelve Kingdoms is a series of light novels by Fuyumi Ono. The first entry in the series ("The Shadow of the Moon, The Sea of Shadow") was published in Japan in 1992; the last volume was released in 2001. The series was published by Kodansha and contains illustrations by Akihiro Yamada.
The Chinese mythology-influenced books were adapted into an animated television series in 2002. The Studio Pierrot production aired on Japan's NHK from April 9, 2002 to August 30, 2003, totaling 45 episodes.
Plot: The anime casts Youko Nakajima, a Japanese girl who is suddenly transported to another world and eventually discovers that she is the empress of the kingdom of Kei, in the role of the main character; however, in the novels, Yoko is only one of many main characters and her story is focused upon in only two novels.
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