How does the author use foreshadowing in Survivor?

In Chapter 47, the reader begins to learn of Tender's great frustration with sex and his desire for power. He enjoys when desperate women call into his hotline, as it gives him the ability to exert power over them. This chapter also introduces the theme of sex and power, which continues throughout the entire novel and foreshadows the problems Tender will have with sex and his own sexuality later on in the novel.