This is NOT normal

(Y/N) (L/N) always have her weeks full of activities such as dance, martial arts and parkour. But when she discover an app on her phone that gives her the power to travel between our world and the world of black butler that is almost 200 years ago. What will happen when she knows what will happen and what will the people think of her. Read to find out. (The front isn't mine. I've only edited it)[Originally from Quotev]