@Kraco - I think that's what Mfauli is saying, that Rimuru isn't a just hero. I just wanted to clarify it.

@Darth - Most of the soldiers he killed aren't the ones guilty of killing his friends and people. He just sacrificed them to save his friends, which has a lot of moral issues.

@Buff - Himmel would not kill 10K to save a few, that's for sure.

The thing is, the story isn't even trying to paint Rimuru as good here. He is in fact a brutal and cruel demon lord, and that means he is evil in many ways, just like all his brethren. It is weird for Mfauli to expect pure goodness from him, but it is also wrong to think everything Rimuru has done is just and moral in many of our human perspectives.