 Why isn’t Charles satisfied with the beautiful woman’s reason for having a romantic interest in him?
A year ago she had been unattainable, a face to conjure with in erotic dreams, far beyond his ken. He touched buttons by the edge of the bed and the illumination quieted to a soft glow, wrapping her in a radiant halo. New York lay quietly below him. She had given of herself freely, warmly, and Charles had accepted. She would have given herself to any man— His thoughts beat a rapid crescendo, activating emotions, stimulating sensations of angry rage. Charles picked it up and folded it across her now cold breasts. A month later the meat animals, the birds and the household pets began dropping as rapidly as the flies which had dropped earlier. And now.... "I've got to find out," Charles told himself.
 Due to the plague that has wiped out all of humanity, Charles is the last man on Earth. She had no choice but to be with him.
 Due to their total immunity to the plague, Charles and the beautiful woman is are last people on Earth. She had no choice but to be with him.  Due to divine designation, Charles is deemed a prophet. She only wanted to be with him for his prophecy.  Due to the plague that has wiped out all of humanity, Charles is the last man on Earth. She had no choice but to be with him.  Due to disease, Charles has become the last fertile man on Earth, among many living infertile. She had no choice but to be with him.