In Jennifer L. Armentrout's book "Apollyon," the Underworld is depicted as a perilous realm where few who enter manage to return. Those individuals who do come back find themselves forever altered by the harrowing experiences they endure while there. The story suggests that the transformation is profound, reflecting the dangers and challenges faced in that dark place.
The quote emphasizes the significant impact of the Underworld on its visitors, highlighting that the journey is not just a physical one but also a psychological and emotional trial. This theme of transformation is central to the narrative, showcasing how facing extreme adversity can change a person in irreversible ways.