Yanderes are supposed to be scary, but I don't get that vibe at all. Usually they only get bad when you're off her route, or she thinks you're off her route, or just if the protag is a bumblefuck who can't figure out how to wear the pants in a relationship.

If the girl's a yandere, and you're on her route, doesn't she basically have everything she wants? So doesn't she have exactly no reason to go postal? What could there possibly be to be afraid of?