Alex, the titular duke is a war criminal:
He ordered:
* the use of hollows point bullets
* the use of exploding small arm ammunition with less than 400g of explosive.
* the use of anti-personnel mines
* Tried to use cluster munitions
* The unnecessary destruction of civilian infrastructure and non military targets. (This is the most debatable,)
There is also the dereliction of duty by not always disciplining his troop for committing other war crimes such as harming non combatant, collective punishment, and more.
By extension Nives also committed some of the same crime.
The characters in the web novel that Iāll release someday, are far worse.
The main character in the prologue casually obliterates defenceless peoples begging for their life, and kills up to 637 people (It hard to say because most of them were reduced to puddles of gore.)(Also they kind of deserved it)
The first regular Pov character might not look so bad on the surface but in actuality he is comparable to the ww2 german generals just following orders. He might not have personally done the horrible thing personally, but him performing his duty to the best of his ability enabled others to commit crimes against humanity.
Finally the storyās protagonist has no qualms killing people around her, having skinned alive three people when she was six. By the time she was sixteen, she had over a hundred kills, with defectors, soldiers from rival organizations, foreign spies, and a couple of her superior officers. Most of them were when she acted as a living weapon for an authoritarian fascist state.