Kougaiji

紅孩児

He is a youkai prince residing in Houtou Castle alongside his father, Gyumaoh, and his mother, Ratsetsunyo.
He is one of the strong-willed youkai with a "heart of gold." He excels in martial arts, can emit fire projectiles, and is knowledgeable in youjutsu, including youkai summoning spells such as his famous Engokuki (Demon of the flame prison).
In Saiyuki, Kougaiji is the enemy of Genjou Sanzou and Sanzo Ikkou (Genjou Sanzou's party) because he is forced to work for his stepmother, Gyokumen Koushou (whom he detests), to retrieve the 5 Sutras, including the maten sutra, from Genjou Sanzou. He does this to obtain a reward from Gyokumen Koushou, who promised to revive his mother, Ratsetsunyo, who has been placed under a curse that turned her into stone in Houtou Castle.
His strong devotion to his mother and kind nature earn him the loyalty of his youkai followers and companions, who are willing to serve him in his task. This includes his half-sister Lirin, whom he cares about very much; his personal bodyguard and swordsman, Dokugakuji, who is more like an older brother to him; and his personal alchemist, Yaone, whom he saved from the clutches of the woman-eating Hyakuganmaoh.

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