Who is Fu Man Chu from Slapstick: Or, Lonesome No More! and what is their importance?

Fu Man Chu is a Chinese official emissary. He makes a deal with Eliza to send her to Mars. He also asks Wilbur to look at hidden papers they wrote as children, particularly their writings on gravity. Fu Man Chu is also the character who notifies Wilbur about Eliza's death on Mars.