Hello Logan. thank you for your comment to my question. I feel pretty better. But the point is that she know only Japan and alone. So,still I am worrying...

Hello Osamu. If it makes you feel any better, I can say that I am relatively young and I traveled in Paris with my girlfriend without any problems. I have also done some traveling alone in foreign countries and did not have any major problems with those travels as well. As long as your daughter does not attract to much attention to herself, she should be fine! If you have any more questions, feel free to send me a message!