I allways (in all games) skip dream (sexual and non-sexual ones) scenes without seeing them, so if I saw her it's unlikely that I will remember it. I don't generally change that policy even in games where they "tell you important things" in dreams. And the dream sex scenes interest me even less than the others. So I'm not going to find out about anything that happens in dreams.
On the other hand, that Nicole "can invade / control dreams, dig out memories and somehow can also disable people outside of dreams" is the kind of thing that I don't really like. Either the MC has some way or power to disable that, or the game is less interesting to me.
This is harem, I don't know if it has romance. But Nicole, knowing nothing about her other than what you said, I know I don't like her.
I'm going to wait to see what the dark turn of the game is like, but I don't know if I'm going to end up playing it (although I liked the little I played, that's true). However, I don't usually like games where the MC doesn't have powers and others do.
On the other hand:
I don't like domination of any kind, or coercion, or blackmail; so I personally think that if the character is as you say, my ideal ending for her is to die (Even without knowing her, I don't consider Nicole an LI, and I prefer that there is no sex scene with her; having unavoidable sex scenes with her is one of those things that I would dislike).
In my case, I prefer to kill the LIs before breaking their minds and turning them into pets. And if I have to kill a LI I will surely quit the game.