candidate: The protagonist is Rutherford Calhoun , a freed slave , who flees from New Orleans on a ship called the " Republic " to escape being blackmailed into marriage by Isadora Bailey , a schoolteacher who convinces Calhoun 's creditor to whom he owes large sum of money , Papa Zeringue , to demand Calhoun pays him all he owes if he will consent to marrying Isadora .