I think it's scarier because she's from 21st century. we live in a world where everyone is equal...well at least more equal than a monarchy. and to go to a place where someone can kill you without any sort of punishment is scary. Literally no one will stop him from killing her. He can kill her any time any day for any reason. You have to out yourself in that century's mindset to survive. You won't last a day frolicking around.
You do realize she has to be extra careful because of her social ranking and as well as her gender. In the old times, women aren’t even allowed to voice out their options/feelings as well as to act on their own. She’s honestly doing a great job to be cautious since people could easily abuse her and her skills
Honestly the MC is great but her hesitance and mousy behaviour kinda put me off. I dont know why but I just can't like her character, especially if she's suppose to be someone from the modern century, like girl where's your pride! she knows so much but doesn't show anything because she doesnt want to be outed and that just makes it more frustrating for me as a reader.