I'll go the uncomfortable route, and say that while (ahem)  there is still a living person left, who can heal and be comforted.
Doomguy leaves cooling corpses, mamono leave struggling messes.
Heal and be comforted can also be attributed as manipulation and brainwashing. Most abusers of their spouses were convinced of themselves of doing the rightous thing. While you can technically attribute death to be 'worse', rape and the subsequent manipulation into normalizing said rape and accepting it from your abuser is pretty damn up there. Sure getting the farm bought for you courtesy of Doomguy is bad, but is spousal rape and captivity something we can even call superior when said comfort is coming from the abuser in the first place? That isn't healing, thats training. See this is where I kinda lose the vision of KC, I want believe Mamono do good, I want to believe Mamono no matter the behavior predicates itself on the welfare and happiness of men. This isn't happiness, its a lie. I'd much rather take the bullet than be tortured into praising Big Brother, I don't care how nice INGSOC's tits are now. It doesn't matter if they feel bad about it, criminal justice is not predicated on feeling shame.
Would it be copacetic if Doomguy were to traumatize and humiliate Mamono, with the promise that these Mamono will be assisted afterward?
Now I'm not into murder spree grimderpery for MGE just as much as the next guy, but, sometimes you need a Doomguy to protect people. Nobody has to die, flip out his buckshot for Demon Realm Silver or something, you know tit for tat.
I'm sorry for the necropost, and this isn't a thing directed or accused at you Justheretowrite from the honesty of my heart, I just feel I'm missing something to MGE.