2/4
So as long as the wielder used it to kill demons and monsters, it didn't care about the identity of the wielder, whether it was a hero or... a Demon King!
The Demon King should have keenly noticed this loophole in the holy sword, and used it to master the holy sword, becoming the new owner of the holy sword with the identity of a demon, achieving this impossible miracle.
And the demon that the Demon King and the holy sword's oath vowed to slay was none other than the Demon King himself!
In this way, because the King was the head of the demon race, he could perfectly attract all the hatred of the holy sword onto himself, not letting the holy sword harm other demon compatriots.
Moreover, under this oath, as long as the Demon King was alive for a day, the purification mission of the holy sword would not disappear for a day, and the King could forever be the owner of this holy sword. No other human could use this sword again!
