What would happen if the world was turned upside down?
Then...
On the possibility that the Oni King's surname is Ubuyashiki and his given name is Yaozai.
Regarding the possibility of Demon Slayer having a violent protagonist named Mukai.
On the possibility of entering a parallel world after dying in battle with the Ghost King——
Yoshiya, the master of the Demon Slayer Squad, was fighting the Ghost King and used himself as a bait. He died in the explosion, but when he opened his eyes, he came to another familiar world?
There are also demon slayers and ghosts here, but the ghost king here is called Ubuyashiki, Yoshiya.
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Simple reversal, don't be too elaborate. The ooc is serious and the short story has been completed.
Intention: The intention is not settled