A truly horrible character is Félix Tholomyès, in Victor Hugo's novel "Les Misérables", the student who abandoned Fantine, and was consequently responsible for all her misery:
Félix Tholomyès — Fantine’s lover and Cosette’s biological father. A wealthy student, he cares more about his own welfare than for his responsibilities. He does not think much of his relationship with Fantine, considering it as "a passing affair." After impregnating Fantine, he abandons her as a joke. Hugo then concludes Tholomyès’ involvement in the story by saying that "twenty years later, under King Louis Philippe, he was a fat provincial attorney, rich and influential, a wise elector and rigid juryman; always, however, a man of pleasure."
(quote: Wikipedia)