Man, power levels are getting way out of hand. And we haven't seen best girl interact with Rimu in like 50 chapters. Feels a waste to be introduced so early to become a mind-controlled puppet to overcome.
I was hoping this wouldn't fall into the trap of other isekai's where they have to make every villain unbelievable strong because the writer decided to make the MC OP. (If Tempest wasn't there, how would the human's even survive the Orc Disaster if not for one of the demon lords taking pity on them )
Also, the world-building is falling apart quite a bit. We are told there are 10 demon lords, all of them with the power of a nuclear bomb (or close to it). So what are they doing? Apart from Clayman, nothing as far as we are told. None of the nations is under attack, neither are they mention to be anywhere. How would the nations not be aware that a majority of the Fullam countries forces left the nation? That's like one of the main purposes of a diplomats/spies.
The story was the strongest when Rimu was starting out and figuring out how to lead his village/deal with the problems that come with managing low intelligence monsters.