(from ebookjapan):
In 574 A.D., a prince was born to Toyohi Tachibana and Princess Anahobe no Mato. This prince, called "Umayado-Oji" (Prince Umayado), who was intelligent from an early age and possessed magical powers, was the future Prince Shotoku, who became so famous in Japanese history for his establishment of the Twelve Crown Ranks and the Seventeen-Article Constitution. His short and tumultuous life was marked by deep compassion and sorrow for all living things.

Note: Comparisons have been made between this work and Ryoko Yamagishi's Heaven's Son in the Land of the Rising Sun (Hi Izuru Tokoro no Tenshi), to the point where there are claims that Ikeda plagiarized Yamagishi's work. In 2007, Ikeda remarked, "A certain mangaka depicted a spiritual romance between Prince Shotoku and Soga no Emishi. I was uncomfortable by that..." while also stating that her take on Shotoku was one faithful to history, since it was commissioned by Shittenoji. Though not named, the mangaka in question was most likely Yamagishi. Yamagishi herself did not comment on the matter.

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