A small black cat that belongs to Dr. Briefs and is practically his constant companion, usually perched on his shoulder. The cat's name is Tama (literally "ball" in Japanese). While the original series leaves the cat's gender ambiguous, the English dub confirms Tama as female—Dr. Briefs even brags at one point that "This is no ordinary cat! She's had 5 years experience!" There's a running joke that Tama somehow understands machinery and repairs, though obviously the inability to talk makes this more of a funny implication than anything concrete.
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