besto

Besto is the plain word for a non-human animal and carries none of the menace English loads into "beast". People are homoj and sit outside the category, which is why bestoj kaj homoj is a normal pairing rather than a redundancy. If you want the loaded sense, the pejorative suffix supplies it: bestaĉo. Going the other way, besteto is a small creature, bestaro a whole population of them, and besta describes anything animal in nature.