How does the author use foreshadowing in The Ice Limit?

When McFarlane learns that Amira has been spying on him, the discovery both tests his trust in her and leads to a sexual relationship. Complications could arise from this change, but it seems McFarlane already sees this and has taken steps to prevent it. McFarlane's reaction to his relationship with Amira, not only gives the reader insight into his personality, but also foreshadows tension in their relationship as the plot continues to develop.