Nina Campbell is the professional assistant to Dick Solomon and Mary Albright, at Pendleton State University. She has a generally friendly relationship with Mary, who was her first supervisor. Later, Dick was assigned to the office and Nina's workload doubled, but her pay did not. Perhaps it is because of this that Nina dislikes Dick so much. She calls him immature and is very cynical and sarcastic when around him. But Dick also mistreats her; instead of treating her like a human being, he decides that assistant means slave. Dick often attempts to send her on errands, such as doing his dry cleaning, or driving him to the doctor, or even ordering and picking up meals for him. At one point Dick fired Nina, but she still had her job with Mary.
Nina works at the University, despite the meager pay that she often complains about, because she is allowed to take free classes. Nina also had a short relationship with Harry Solomon, before chasing him out of her apartment after finding the money he had left under her pillow. Harry had left the money there in lieu of the tooth fairy, but Nina misunderstood the gesture.
Sally Solomon considers Nina to be one of her best friends and often goes to her for advice. Nina not only advises Sally but she advises Mary as well. In fact after Mary found out that Dick was "married" it was Nina who encouraged Mary to go out with Dick again after his "wife" had left. She is often very firm when advising Mary, but almost always right in her judgment.