Evan wasn't mishearing it, was he? The other female voice really said Spire?
The very same person that he had found in his bedroom after she went in their house to seek refuge after escaping her kidnappers? That Spire?
"Maybe it's not just here." Spire replies, a small sigh can be heard. "We've been for a while, Camela. Maybe we should try other bookshelves and hope we'll find it there."
The female conversing with her, apparently named Camela, sighs back. "Fine. You look at the right corner. Spire and I will be on the left. Tell me when you find it. We'll meet back here."
When the instruction was given, Evan saw that three yellow opaque dots finally started walking towards where they will search next.
He waited for them to pass by him to make sure that he won't be noticed if he does move. And when he saw that they were far enough away, he closed the map and went towards where the last books were.