At the end of the world, the main plot follows one male lead and two female leads, while the Zombie King and the pair who land in Antarctica form the hidden storyline. The book includes a chapter about aliens to explain the story's plausibility, along with superpowered people and robots. In the end, the aliens destroy Earth, leaving only Antarctica. Finally, the protagonist and the female lead, perhaps joined by a few more female characters, take shelter beneath Antarctica's frozen ice and begin a happy, primitive life all over again.
It's a very good apocalyptic novel. The more I read, the more I read it. The more I read, the better it gets.