That's some edgy BS he is spouting about, "An enemy? Kill them!" He might be right about that other guy not liking the willingness and the act of killing, but that doesn't make "Kill all of your enemies." true. Imho If a person isn't a danger anymore or only a really minor danger, let that person live. You never know which opportunities might arise. Maybe her friend is reasonable and THE bridge to peace? Maybe she switchs sides and reveals information. Maybe she can be exchanged to something important or you can pretend to exchange her, so the enemy brings that something into striking range? If you kill someone, you can't undo it. You create the worst kind of bad blood. ... If that person is dangerous though, e.g.somebody who will most certainly aim for you or your beloved ones in 20 years or now, as he/she is somebody who will get scot-free, unpunished by the law or the circumstances, or somebody, who will continue to be a danger to other people (a bandit that would escape otherwise), well that's a different story.
I can give to MC, that he has zero trust in that law systema dn it's ability to keep her contained. That bitch, that tried to murder everyone, might come back later and aim for him. But I can't let him get away with that self-righteous speech. Also everyone, that gave in to it and called out that other guy in this story is an idiot. You either feel, that is isn't right to kill helpless people, or you have your personal reasoning.That BS-speech of MC is just cringey.