Crack fic idea where KDJ dies and is isekai'd into a world as the classic "evil", final boss, demon king with a huge harem (for some reason).
The twist: all the members of the harem are variations of YJH cast in different roles to make it seem like they're different people, even though they all have relatively the same looks and personality.
(The meta reason the whole harem had to look like YJH? If there was only one YJH, then the harem would be obsolete. The demon king KDJ would be in a monogamous relationship with him and the harem would be disbanded.)
By the time the hero party reach the final boss to defeat him (and free the members of the harem), the YJHs have already fallen in love with their foolish demon lover, who is equally smitten with all of them. All the YJHs are fully prepared to fight and defend their lover from harm.
(Also, it's impossible for KDJ to have committed any of the crimes the heroes are implying he did. He doesn't have enough time to. The YJHs keep him very preoccupied, thank you very much.)
