Mappa Douji (麻葉童子) is a manga created by Japanese manga-ka Hiroyuki Takei. It is one chapter long and tells the tale of Asakura Hao, a Shaman King character, in his childhood 1000 years ago. In this original incarnation, his name is Asaha Douji. He was named after his mother, Asanoha Douji, who was killed by humans for being a Yōkai who could see and speak with demons. After his mother's death, Asaha is left with no home and no family.
He later meets and befriends a demon named Ohachiyo who renames him Mappa Douji (Demon Child), to avoid confusion between his and his mother's similar names, as the kanji could be pronounced both ways. Ohachiyo teaches Mappa Douji many things, and towards the end of the story he allows himself to be used in an oversoul, which additionally gives Mappa Douji the Reishi (霊視, Reading the Heart) ability, the source of Hao's future insanity.
- Asaha Douji/"Mappa Douji" - Asaha is the fist incarnation of Asakura Hao. When first introduced, he is a hateful child because humans had killed his mother for communicating with demons. After his death, Asaha comes to despise his own humanity, making it his mission to wipe out the human race for being so ignorant.
- Ohachiyo - Ohachiyo is a demon that had roamed around for 200 years before meeting Asaha Douji, who he gives the nickname "Mappa Douji" due to his confusion about Asaha and his mother's names. Ohachiyo teaches Asaha how to write, count, fish, the names of hina dolls, birds, and how to make an oversoul. This also grants him the mind-reading ability of Reishi. He tries to persuade Asaha not to feel hatred for humans because they fear and dislike what they don't understand, but at the end of the story we find that Asaha could not accept this and their friendship falls apart. His spirit energy is unintentionally consumed by Asaha at the end of the book, cursing him with a permanent Reishi.
- Asanoha Douji - Asanoha was Asaha's mother. She was killed by humans (specifically Monk Densen and his guards), who burned her house down for being a Yōkai.
- Densen Hoshi - A monk of the Heian period that specializes in exorcisms. He proves to be a fraud during his confrontation with Asaha and is killed by him.