These characters are from "To Kill a Mockingbird". In the story, mockingbird is an idea of innocence. To kill a mockingbird indirectly implies to destroy innocence.
Bob Ewell was a cruel, abusive and ignorant drunkard and who does not care for kids. He accused Tom Robinson of raping his daughter, Mayella. Ewell later attempts to murder Jem and Scout Finch with a knife. But were saved by Boo Radley who killed Ewell with the knife.
But the sheriff made an official report that Bob Ewell fell on his own knife and died unattended to.
