Slander
Ero suggested to the king that they summon demons to help defend the kingdom against military aggression from Elsaland.
The increasingly decrepit king seemingly happily agreed, but he was actually so old that he just nodded in agreement with everything. He actually had no clue what Ero was saying, as he was almost fully deaf.
- Please read this book to complete the mission
Ero actually planned to use the dark energy of the demons to weaken the seal of the Devilish Volcano. He wished to awaken the Evil Dragon.
But oddly, no one in the court tried to stop this strange advice from being put into action.
(You started to wonder who had authored this book.)