Most people wouldn't have genuinely meant that Hogwarts: A History was interesting, but Rei knew better than to assume the same with Luna. She was the type that was interested in knowing all of the smallest details about the school. It wasn't something that Rei had a particular interest in researching but she could understand Luna's point of view.
"At the very least, I'm glad that it's interesting," Rei noted. "This one will be good for me to learn about the different paths I could take." She patted the book in front of her.