The End of the World? He Leveled up with Her!

All the technologies that exist in human society will collapse in just an instant. Healthcare, electricity, everything is gone. In this apocalyptic world, many human beings have begun to realize the existence of "serial numbers". Far beyond human cognition, with the ability to change humans, magic? Science and technology? Monster? Survive and evolve! Everything is changing the original direction of the world... This novel and its characters are purely fictitious. Any similarity is purely coincidental and should not be imitated.