Alternatively, maybe the stone is a powerful relic that the Scarlet Demon uses to control areas, and Sasha must destroy it to liberate the people. There could be a twist, like the stone was misunderstood or had a trapped spirit that needs to be set free, requiring a sacrifice from Sasha.
Possible conflict: the Scarlet Demon is not just a villain but has a backstory. Maybe he was cursed long ago and now seeks redemption. The stone is keeping him in a monstrous state. Saint Sasha must find a way to free him from the demon's curse. Or maybe the stone is the demon's prison, and freeing it would unleash it unless she does it properly. Saint Sasha and the Scarlet Demon-s Stone Free ...
“” it hissed, as the gemstone cradled in its chest—its cursed heart—began to crack. The light seeped into those fractures. “ This feeling… is this… peace? ” Alternatively, maybe the stone is a powerful relic