Mrs. Frink is a radio personality who is the wife of Professor Frink.
After demonstrating his death ray to Grampa, Professor Frink says that his wife will be happy with the invention, because she has hated the whole death ray thing from day one.
When their son crashed through a window during a demonstration of a radio-controlled airplane for babies at the Baby Expo, Professor Frink says, "Oh, dear. My wife is going to kill me."
When Professor Frink bought Simpson & Son Revitalizing Tonic, he doubted its effects. However, when he drank it, he turned into a handsome man and, with smooth voice, asked his wife to have a wild wingding at the cyclotron. She agreed giggling and the couple left.
In much later episodes Johnathan Frink Jr has a robot wife. Meaning perhaps their marriage went sour.