Then if I may suggest, change consistent to thorough. I think Orin here means that humans (or at least the human spirits) will always finish the job they set out to do, not giving the same responses to the same stimulus all the time, especially that she later says "That's humans for you. Even their answers vary." Given the tone it was spoken in and the context, I'd say "Humans, they sure are thorough" is a better translation.
Oh, enough!Is she out to die again in someone else's body?Humans are scary—they don't hold back when their backs are to the wall.Humans are thorough.That's right.