Aside from being an infrequent surname, and an occasional nickname for ‘Hubert’, ‘hube’ has been used in several published stories (mine) to mean exactly ‘a human being’, opposed to ‘sim’, meaning a simulation. That is, to emphasize, ‘hube’ is not a synonym of ‘human’ (adjective), but of ‘human being’ (noun). Some of my readers have considered this use of ‘hube’ demeaning, but I don’t mean it that way; just the opposite. ‘Hube’ avoids the disparagement of using an adjective as a noun as if beings were just this adjective, and having said that you know everything you need to know about them **. Besides, if you’re careful about language you might understand that there’s a hint of illiteracy in using ‘human’ as an adjective (from humanus, not from homo).
** Consider ‘cripple’ as an example. You would never use ‘cripple’ as a noun referring to a person, would you? (SOED: “A person (permanently) impaired in movement by an injury or defect, esp. one unable to walk normally. Now regarded as offensive. “)
For useful discussions see Fowler, third edition (Burchfield), page 367f, and American Heritage Dictionary, first edition, page 640.