This feels parallel to what I eventually worked out about which Stories About Bad People Doing Bad Things I like and which I don't: if it's clear that the author knows that these are bad things, I'm liable to enjoy the story; conversely if it's clear that the author actually thinks these are good things, I'm liable to get creeped out in the worst way. I don't need to be hit over the head with morality, I just need to have the feeling that, however much perverse fun we have writing/reading about it, we're agreed that it shouldn't happen in Real Life(TM).