" Dragon Lady" as a term could refer to a stereotype of East Asian women as mean, deceitful, domineering, or mysterious.The term's origin and usage is Western, not Chinese. Inspired by the characters played by actress Anna May Wong. The term was coined from the villain in the comic strip Terry and the Pirates.
The term was applied to powerful Asian women and became part of the American slang in the 1930's.
If your quotation is from the character in the popular U.S. comic strip Terry and the Pirates, then the Dragon Lady refers to Madam Deal,
a beautiful, seductive, and evil Asian woman.