How does the author use foreshadowing in Enna Burning?

The Prologue introduces an unidentified woman who is walking away from the burning. In this section, she recalls the horrors she has caused as she struggles into the woods, burning from inside, and buries the vellum containing the mysteries of the fire. This scene foreshadows the events to come, as Liefer discovers the vellum, an occurence that will direct the story's events.