I'm the Dragon King & Legendary Healer

The second daughter of a financial magnate passes a reward notice in the street and near it finds a beggar holding a worn bowl. She drops a few coins in. The beggar tells her that for her kindness he will grant her one wish, and he follows her home. The man in the rags is the founder of the Dragon King Consortium, and he is also a physician. He had watched the world turn selfish and grasping and had given up his old life to walk the streets in disguise, helping the kind-hearted people he ran into get what they wanted. The magnate's eldest daughter has a rare illness. Her father posted a large reward and brought in the three most famous doctors of the day, the ones people call the Medicine King, the Medicine God and the Immortal Physician. None of them found a cure, and the father had given up hope. He does not believe a beggar can do what they could not. The beggar treats her anyway, and she recovers in front of the whole house. The father offers him his daughter and his fortune. He turns both down because he is already engaged. When he goes back to set a wedding date, he learns that his fiancée has broken off the engagement and chosen his old friend instead.