Beatrice looked around as they walked through the kitchen, until Alucard asked her his question. She thought about it, trying to recall the story he mentioned, and she answered "I think I have...or at least variations of that story," She remembered that the Brotherhood, when asked about the story, tried to either deny it, or tell different variations of the story. 
She wouldn't admit it out loud, but the story of this knight, the Brotherhood, and the Lords of Shadow, was sort of her inspiration for her scientific work she did eight years ago. She thought that if she could separate the darkness and light, the good and evil, of human hearts, then society could live without having to go through the pain that the knight went through. How foolish and she was naive then, and now she paid the price.