A+
Of course someone might say both are demons and therefore both evil. But the arch demon doesn’t have the same power, or even the same motives, as Satan. Can’t do as much damage, doesn’t have the authority level Satan does. The core of his evil isn’t the same, he got corrupted because he followed Satan, Satan was corrupted by himself wanting to usurp God and take His place.
I suppose you could use “Satan” and “Human Satan worshipper” if people objected. Even “Human Atheist” or “Humanist”. Look at what these people propose as good.