The MC, whose life has been ruined by the villains, instead of the delusional moralist reader's desire of forgiveness, decides to take revenge and dish out suffering to his enemies. At the same time, the MC can demonstrate acts of kindness to those that aid him in his goal.
Many people would just focus on his overpowered ability and think this story is just about the MC forcing things through with it and doing whatever he wants with it. This is a superficial conclusion. In actuality, the cunning and scheming element of his character is the force that drives this story forward. This is where the whole sexual violence and gore element, the thing that many readers don't understand the reasoning behind of, comes in. It's made to break the villains, just like they broke the MC. As a matter of fact, when the simple sexual violation didn't work out against the warrior girl he decided to play into her desires of the princess to the breaking point, which is when she let go and get devoured by the beasts.
I'm also glad that there might be a continuation of the series from the words of the demon lord and I'll probably start reading the novel just so I can know what happens next.
There are, however, some areas where the story should be done better. It would be better if the story went into a little more detail when it came to the backstory of the princess who, in the past, understood him only to then get assassinated. The most important criticism, however, is that it always feels as if the MC has the road laid out for him to follow, without any notable blocks to his path except time, meaning that the whole story ends up being dragged out more than it should.
I heard there will be an anime about this, which I hope won't beend over for the usual cliche / niceguy audience