Housei Sanagida
Director of the Sasanagi Hospital, and a subordinate of Zeppeli. He is the Mad Scientist archetype and is trying to discover the secret to immortality. He noticed Hiro's immortality and tried to conduct brutal experiments on him. He was killed by Hime with a defibrillator but revived himself with the drug Trioxin. He was defeated once again when Flandre exploded a roomful of lime dust. (Source: Wikipedia)