You were never expecting that. 'Kimetsu No Yaiba' aka 'Demon Slayer' was your sister's and your two Friends' favorite anime of all time. You were not a fan or a person who liked anime and cartoons like this, but you were aware of the plot and some characters. And you liked it a little. Very little. But you, your sister, or your friends were never expecting that the main antagonists of That anime; the Great DEMON KING and his UPPER MOONS would appear in your world and live with you all.