The Heart Demon Curse, insidiously pervasive, could spread unnoticed throughout the world. But frankly, this magic spell merely transformed the soul by eliminating the "uncertainty" within the soul's calculus. In the early stages of being cursed, there were some laws that one could apply by sacrificing certain parts of the soul to break free, and there was a slim chance of demolishing the illusion through sheer will and wisdom. Ultimately, mortals primarily rely on their brains to think; even if affected by the spell, they wouldn't lose their self-awareness but would merely be influenced.