Red Boy, son of the Bull Demon King and Princess Iron Fan, was a powerful demon who had cultivated formidable magical abilities. He coveted the flesh of the Tang Priest, Sanzang, believing it would grant him immortality.
One day, spotting Sanzang and his disciples approaching, Red Boy devised a plan. Knowing the disciples' combat prowess, he decided to exploit Sanzang's compassion rather than use force. He transformed into a seven-year-old boy, bound and hanging from a tree, and cried for help.
Hearing the cries, the kind-hearted Sanzang ordered Monkey to rescue the boy. Monkey, recognizing the demonic disguise, warned his master. Angered, Sanzang instructed Pig to free the boy and then ordered Monkey to carry him. As they set off, Red Boy leaped into the air, leaving a magical double for Monkey to carry, and summoned a whirlwind to abduct Sanzang.
Monkey immediately pursued the demon to the Huofang Cave in Withered Pine Valley. A fierce battle ensued. Unable to defeat Monkey, Red Boy unleashed his most potent magic: three types of mystical flames so intense that even the Dragon King could not extinguish them. Forced to retreat, Monkey sought help from the Goddess of Mercy, Guanyin.
Guanyin subdued Red Boy and took him to the South Sea. Monkey then rescued his master, and the pilgrimage to the West in search of Buddhist scriptures continued.