Cheoyong (處容) is an admired figure in the Korean pantheon, and his dance is performed to this day. According to record, he was a son of a sea dragon and appeared before the King of Silla in the 9th century dancing with his brothers.
Cheoyong remained at the capital to serve the King, who gave him a wife. Yeoksin was smitten with her beauty and Cheoyong came home one night to see Yeoksin lying with her. The dragon's son withdrew dancing and singing without confrontation, which shamed the god into swearing not to cross a threshold if he saw Cheoyong's face.
That was how people came to put up paintings of Cheoyong to repel smallpox, and his dance was performed for luck. I have written more about Cheoyong's story here: https://ljwrites.blog/posts/cheoyong-story/
