The Twelve Kingdoms - Shadow of the Moon, Shadow of the Sea: Part 1 novel volume 1 was written by Fuyumi Ono with illustrations by Akihiro Yamada and features an all-new translation.

When high school student Youko Nakajima is approached by an enigmatic, blonde-haired stranger named Keiki, her life is turned upside down. Whisked away into the perilous world of the Twelve Kingdoms—a realm teeming with mythical beasts, ancient prophecies, and political intrigue—Youko finds herself alone and hunted. With danger at every corner, she must fight to survive, all while grappling with shocking revelations about her true identity that could shatter everything she thought she knew.