Hey, I see your point, but it's not an attempt at humanizing them and making you feel bad. They rape like everyone in that world (even the Champ whenever they play a victory scene), but that doesn't mean that they'll just cheer for you while you kill their partner. No matter how good or bad of a person you are, getting angry at someone killing your partner is what I thought to be the appropriate response.
About the "you don't have to do this" I think you may have a better point there (though keep in mind that one of them calls you a monster after that and once you've already killed the other in front of her. Again, what I feel it's an appropriate response to that). I added the "you don't have to do this" part because I didn't want a single [Kill them] option and then getting them killed immediately after, because I've mistakenly clicked on an option before and, in this case, that mistake would cut you out of more content in the future, so I wanted the option to go back before that. But yeah, maybe I could have handled it better.
