SPOILERS BELOW
I just finished reading this. It's hard to put into words how this made me feel. I'll try anyway.
One thing I loved was the Angel telling Harmonica that no matter what, she will never even get close to Sicil. I find that deeply sad for her. It's like no matter how much good she does, and how much she cleans up after herself, a vital part of her will never live up to "true goodness", if that makes sense. Both Sicil and Harmonica are doomed from the start, and there is absolutely nothing that can be done to change that.
That Harmonica's desire to kill Sicil stems from such simple frustration is genius. There was no big falling-out; they didn't even know each other. Sicil doesn't even recognize Harmonica when they meet again on the bridge, either. That's the whole crux, isn't it? Harmonica put so much value in a person she thought was below her that she thought killing her would be fine.
Everyone is truly normal in this VN. Loved it, and was close to tears by the end. (And I will also be thinking about the significance of the woman who sometimes appears in flashbacks and at the end ... In fact, this entire story will stay in my head for a long time.)