THUVIA, MAID OF EARTH by Tyree Campbell
A solar mass ejection is about to incinerate the Earth and almost all life will die. Thuvia is a highly gifted teenager who has a plan to survive and to repopulate the species—a plan for which she’ll need help. For this, she thumbs a ride, to abduct the first man who comes along, for there’s no time to be picky. But the two have cultural differences—she’s practical, he’s older, and straight-laced.
Maybe they can survive each other. But can they survive an Earth that plans to kill them both, and thereby complete the extinction of the species?