Ano, the case of the duke-sama isn’t really worth to think about. It seems His Majesty, having gotten tired to deal with him, was waiting for an opportunity of him going on a rampage.
As he was a person having many problems, mainly with women and money, beforehand, when he suddenly targeted me, it ended up in a grand self-destruction.
That strangely high reward apparently was also a way of thanking me for saving the national finances of going bankrupt due to the Duke Hertha household.