Dalian from The Mystic Archives of Dantalian ("Dantarian no Shoka") fits all three of your requirements. She has really long hair and is basically the show's version of Victorique from GOSICK. Also, she is the keeper of phantom books that sometimes kill the people that read them. And lastly, she is known as the "Black book princess/ Black Biblioprincess"
And in episode 9
In terms of emotional elements, most of that comes in the last episode when