Allegory

Jimmy Akin, "John Paul II on Allegorical Books of the Bible":

He didn't give an exhaustive list of allegorical books (many would put the book of Job into that category), but in 1985 John Paul II gave a brief review of the books of the Old Testament in which he stated:

"The Books of Tobit, Judith, and Esther, although dealing with the history of the Chosen People, have the character of allegorical and moral narrative rather than history properly so called."

Why would he say this?

Tobit, Judith, and Esther all contain named figures — some of whom are known to history. They mention real places. And they refer to datable events. So why would he say they are allegorical rather than history proper? What cues in the text would reveal that?