Seventy years ago, many humans took part in a game. Marked by tattoos, people tried to kill one another to breed greater power and escape their lots in life. As a result, a catastrophic event occurred. Reborn from the cultivated powers, a demon scorched the land, evaporated oceans, and brought overall ruin to Earth. Humans have become all but extinct, and as a result, Lydia has grown up without knowing her parents. Raised by her grandparents, she lives and trains in one of the last bastions of humanity, working to become a great blacksmith like her grandmother, blissfully unaware of her lineage, and her fated role in restoring a barren Earth.