What is the story of Marilene O'Shay's mummy in the novel, Meridian?

The supposed mummified body of Marilene O'Shay is an exhibit in a traveling circus. Marilene is said to have been an unfaithful wife, who was killed by her husband. Her husband, on the other hand, was forgiven by the law and the people because his wife was unfaithful. The flier says that her blackened skin reflects her sins. Black children are only allowed to see the mummy on certain days, and Meridian leads a protest against this. The children who see the mummy say that it's a fake made of plastic.