Hey about your Dark Tale of Deception story rewriting.
If not only Malak's realm, but the ones of every other demon, has been sealed away, that means there's more than Malak's monsters and more than just Malak as a leader, right ? How would it work, politically speaking ? Is there like, a council of Demons ? Did they wage war in lock-up and Malak managed to get the power ? Does every demon plot on betraying each other and especially Malak ? Did they force him to take all the responsibility for what happened to their realms, and to fix it all up ? Is he cursed physically because of last suggestion ?
I may be thinking too much into it, but I like when everything clicks together.
He tried to warn all the other demons about the mortal uprising, to no avail. Everyone laughed in his face, only for them to get one last "I told you so".
All the demons end up being stripped of power (they get SOME of their abilities back, but they have to develop a magic system instead of having power in them), so they turn to Malak. He warned them, he knew before hand, and he had the best strategy when it came to battle bc the ones leading were the souls he claimed.
Some demons want him to take responsibility for their realms, yes, but many of them agree that his head is screwed on better. Not smarter, just actually USES it, even when caution seems weak.
The demons planned to betray each other in the beginning, believing that they wouldn't stay trapped for as long as they did. But after a community was formed, power was hard to worry about.
Basically, everyone else shoved everything on Malak, and he ended up being a good king by demon standards. After bierce came along, he became likeable by the people. Not just as a person in power, but as a genuine ruler.
After the royal sisters deaths, it made more demons give up on power, because of the stress they saw their temporary king under.
TL;DR
Malak was made king because the other demons failed to prepare like he did, out of believing that worrying about the mortals defeating them was the mindset of someone weak.
But he was right in the end, and all the other demons were salty. They DID plan on betraying each other, but went against it after living rather peaceful lives.
They all then REALLY didn't want to get back into power, seeing how having the power over demon kind messed up Malak during his time of grieving.
Bonus:
Since you mentioned it, some of the demons do work as a council for Malak. They stick with their own monsters and territories, but come to him with problems
