The black cat, also known as von Schwartz, Cat #0 and Mirci #1, is the only (originally) male feline inhabitant at Piszkéstető Mountain Station. Of course it basically makes him an eunuch, but don't call him that. That would be just rude. You could call him(?) a 'gib', but the black cat does not understand English. Or does, but doesn't care. Like about anything else. He prefers Cat #0 (over Mirci #1) for obvious reasons: he's black, so it's kind of obvious to call him that (and Cat #000000 would be too long to pronounce); he is (was...) the alpha-male of the pack, therefore the first index number is his by definition, and every honorable programming language starts indexing from 0; it is way cooler.
His sole purpose is just to terrorize the other constant inhabitants. Well, mostly Microficus, as she's the smallest, and Cat #0 hasn't got the balls to properly bully everyone. Also, usually he is the first to arrive when it's feeding time.
Status: MIA. Rumor has it he turned traitor and now serves the owner of Vöröskő restaurant. In case of contact, follow protocol regarding deserters (i.e., kick him in the ass). At that place, Black (von Schwartz, Cat #0 and Mirci #1, ...) is called Bagira. This name does not make any sense, of course.