Dr. Fooler is another of Tezuka’s mad scientists. Childish, both in his appearance and in his behavior, he is nosy and pushy and often worms his way into business he should not be part of, or pushes forward ill-conceived scientific projects against the better judgment of wiser scientists.
He appears frequently in Astro Boy (1952-68), though generally not as a villain but rather as the accidental cause of great calamities. However, he is probably best known for his recurring roles as Dr. Kani in Black Jack (1973-83) and as Dracula‘s hemmorhoid-plagued, vampire-hunting arch-nemisis, Professor Hellsing in the comedy Don Dracula (1979).
(Source: Tezuka in English)