Lupus originally sought Professor Milo's aid in treating his severe migraines. Milo discovers the cause of Lupus' migraines is that the man had lycanthropy. Milo would use a serum derived from an Alaskan timber wolf to accelerate Lupus' condition, turning him into a full werewolf. Milo blackmailed Lupus, telling him he would have to kill Batman, who was an enemy of Milo, if he wanted the doctor to cure him. He fights Batman until he is struck by lightning and is presumed dead. In fact, Lupus had survived and went to to Alaska, hunting the wolves there in an attempt to find a cure for his condition.
Later Lupus' sister, Angela, would require a bone marrow transplant. Batman sought out Lupus to aid his sister, but Lupus was content with his new life in Alaska and had no desire to leave. Batman eventually subdues him with the use of a silver net. After their return to Gotham, Batman promises Lupus that he'd find a way to cure him.
A man named Anthony Romulus was used in Batman: The Animated Series. He has an extremely similar origin.