it's different than how it happened in the web novel. I hear he eventually kills her during a duel later on in the WN.
I suppose it makes sense that the author would want to find a way to have their cake and eat it too, although personally, I feel like not having any agency makes her character way less interesting. If someone's gonna be a villain, let them be a villain. People who treat children kindly can still be horrible murderers without any kind of mind magic.