Hermione had been working in the Department for the Regulation and Control of Magical Creatures since completing her NEWTs and joining the Ministry. Her original intention was to continue her work on S.P.E.W, but after hitting a multitude of roadblocks, she decided to shift her focus and regroup at a later time when she had more experience. During her time exploring other areas of the department in which she could enact change, she stumbled upon the shocking lack of information on vampires. As she made her way through the slim stack of files on the creatures hidden in the depths of the endlessly expandable filing cabinets, she realized the Ministry was hiding something. While vampires were known to be mysterious and private beings, the purposeful lack of information captivated Hermione, and once she latched on, there was no letting go.