Honestly, I don't think Alvina has done anything potentially harmful/evil to MC yet? Apart from not liking the MC, and trying to distance Seven from a person, who Alvina believes is bad... They did nothing.
Seven, however, is a completely different beast. I agree that they's no saint, but I never felt like Amy was trying to make them look like one. Maybe it's because I'm not a native English speaker, and so for me, something gets lost in translation. Who knows.
As I said, I don't think Amy really thinks of Alvina and Seven as a perfect match. Would I like to see them together? Absolutely not. But I don't think that's the point of Alvina and Seven.
Their POVs seem to go like this: Alvina wants to replace the MC, perhaps without realizing it.
Seven though, no matter how "close" he says they are, never seems to really open up to them. In one of the POVs, if I'm not mistaken, Seven himself says that Alvina can't understand them. Something like that.
And I mean, Seven is hypocritical. And what happens when you feel betrayed and you're dependent on someone.
I say this because when I was younger it was the same as Seven.
She was a girl who gave everything for the people close to me, especially those I was dependent on. In that moment, you feel betrayed, as if someone had stabbed you in the heart. Your entire psyche changes. That person who once brought you happiness has now caused you unimaginable pain. It doesn't matter if it was a small, silly matter.
You feel like the air is missing. The ground beneath your feet. It's as if someone has torn a part of you away, leaving you in pieces. And that's where anger kicks in. The desire for revenge kicks in. You want that person to feel even a little bit of the harm they've done to you. What if they do the same thing? Even worse, because you don't think logically.
That's not an excuse. Of course not.
I don't think Amy really changes her mind, but we'll only really know that later.
I can think one thing about her, you another... But in the end, none of us really know what she want for her characters, for the story, and what she really think.
Of course, everyone may or may not like the way she approaches questions. I wish she were clearer, But I don't have any problems with the way it interacts either. As long as the story is written coherently.