The Netherworld: A world inhabited only by Demons, creatures born from the dark abyss. For Salvos, a curious newborn Demon with a penchant for making friends, surviving this hellish landscape was always going to be a difficult task. And when her companion's life is threatened by a mysterious Demon King, she'll have to adapt, gain experience, and evolve to do what it takes to save him. Even if it means separating from him and being tossed into an unfamiliar world with Humans, monsters, and a bright blue sky where she is scorned for being born a Demon. After all, the law of evolution is survival of the fittest, and Salvos will survive.