The First Guardian of the Abyss is a being of enormous strength and incredible skill, an absolute warrior whose sole purpose was to guard the gates of the Abyss. Epochs succeeded each other, the cycle of time intertwined the world, people were born and died, civilizations flourished and disappeared into oblivion, and only the First Guardian remained unchanged. Only once, the First Guardian was betrayed by his comrades, and the entrance to the Abyss was open. An unimaginable monster appeared from the open gate, trying to devour and destroy the world. The brave guardian, a warrior without fear or reproach, rushed to stop the monster and close the gate, but the traitors sided with the fiend of the Abyss, delivering a vile blow to the back. When the First Guardian came to his senses, he ended up in the body of a person, or rather, a ten-year-old sick girl. (This book is not about gender change, because the First Guardian was not originally a human and had no gender.)