A resident of the Floating Castle that battle demon beings, the girl Rasutel (Rasu), chosen by the willful lady, the Demon-Breaker sword, is sent on a quest to save a princess kidnapped by a Youki. Her quest is helped by a mysterious Youki called Anshu (but he has basic color that usual Youkis do not have.... hehe!). She is also hampered in her quest by her demon-being oriented younger brother who seeks her golden eyes, the heritage of their father, the Golden Youshu.

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