Frank is, at his core, the monster from Mary Shelley's Frankenstein. It's the inspiration for his creation; Von Hatecraft happened to read the book (and mainly watched some of the Boris Karloff movies) and was inspired to create his own man, simply to prove that he could do it. However, once he was born, Hatecraft neglected him almost immediately and left him to Vigor, who quickly and efficiently takes it upon himself to teach Frank about the world..and also to vent their general contempt against Hatecraft. As a result, Frank is quite melodramatic, apathetic and philosophical.