Honestly, she feels like a genuine moron. And it makes her unlikable. "Haha, so funny. The murder rapists want to do horrible things to my mom and sell me and that other dude into slavery!".
I can't really dislike her, maybe it's the kid hormones, maybe it's that she herself feels that she is overpowered and doesn't take stuff seriously, maybe its both. My problem is that the author makes all these horrendous antagonists, makes it seems like they have some insidious plan but Millie always miraculously catches them.
I was expecting them to catch and move her to their inn, obviously I don't want her or her mother to get raped, BUT I was expecting the author to show her that not everything is shit and giggles, you have to deal with these shitheads so that you and your family are safe. TBH my biggest problem is that the author has done this multiple times and I'm always like "oh the previous 2-3 shitheads failed, this guy might actually do something to her for real" but its always played like a bad gag.
tldr: i was expecting her to get kidnapped and get a life lesson about how life aint shit and giggles even if you are OP.