Magic circles in Korean fantasy usually either respond to tiers - like levels in DnD - fireball being 3rd level spell and all that...
or very often refer to quite actual magic circles that are engraved on the heart or soul or condensed using mana. In these settings it usually allows for control of larger amount of mana or something along those lines...
btw isn't there a novel of this, It doesn't seem like translations will be reasonably quick or regular