The Shadow of the Moon, The Sea of Shadow(月の影 影の海Tsuki no Kage, Kage no Umi) is the first novel in The Twelve Kingdoms fantasy series written by Fuyumi Ono. The Japanese edition split the novel into two volumes, but the English edition combines them into one. The first volume is divided into eight chapters. The epilogue, the Red Book of Kei, retells the politic events between the fall of the King of Kei and Yoko's ascendance to the throne. The book was published by Kodansha on June 20, 1992. The English language edition is published by Tokyopop under the PopFiction imprint.