there is at least one character in pokemon who just straight up is therian. like that's just the correct word for it. they're a nameless npc who says that they want to be a pokemon and you can tell them "you can be!"

and they answer that like "oh you're right i can just live as a pokemon no matter what ^^"

what i actually meant was "go to kanto and talk to my buddy bill" but the way game freak wrote it seems to be that they're just a therian character