How does the author use foreshadowing in The Satyricon of Petronius / The Apocolocyntosis of Seneca?

In a comical incident with a young boy, Encolpius' impotency issues emerge. The young boy wants gifts in exchange for sex. When Encolpius runs out of gifts, the boy warns him to leave him alone or else he will wake his father and tell him. Ironically, the boy begins wanting sex more than Encolpius and keeps waking him up. Finally, the exhausted Encolpius tells the boy to leave him alone or else he'll wake up the boy's father and tell him. This section, though comical, foreshadows a later story where Encolpius' impotency needs treatment.