
so far this is how i understand it
the first concubines guardian mage is the one who played a big role on stopping the demon but when he disappeared he was appointed as the first concubines guard so when she told him abt the ring he made it and he put the anti-demon flame spell on it so that if the documents about it were destroyed and if he was ever killed there will still be a way to stop the demon
i know this might be wrong since this is just another guess
i dont want mikado and shiki to be enemies like i have a gut feeling mikado wont kill shiki but i feel like sumtin bad gonna happen to mikado and idont want that i like their friendship