In this world, there are monsters, demons, and gods, and lastly, humans. There are Dungeons where Adventurers go to acquire skills and power. And there are mysterious Labyrinths where one can inherit the powers of demons and gods. The father of all humans, Zeref, grants each human a unique skill.
We see a small village with lush greenery, where a small orphanage is located. Inside, we find two kids, a boy and a girl.
[Leap forward]
We see the boy, , receiving a unique skill a slash in a Church, and the girl with him receiving Divine Healing.
[Time skip]
Rio, an orphan with striking red eyes and black, brownish hair, is a handsome young man desired by every girl. He has a childhood friend, Saira, with stunning white hair, golden eyes, and smooth skin. She is a B-rank Adventurer, while Rio is a C-rank Adventurer. On Saira's birthday, they embark on a monster-hunting quest. After killing several B-rank Fire Wolves, they head back but stumble upon an invisible door that only Rio can see. He touches the door, and it opens.
[System initiated]
Rio: "What are these sounds?"
[Beginning transportation]
Rio: "Saira, can you hear them too?"
[Adjusting language and comprehension]
Rio: "Where did you go?"
[Injecting memories]
Rio: "My head is hurting."
[Process complete]
Rio: "All these memories..."
In the distant past, there were only two True Gods: the God of Evil and the God of All Creation. The evil God was extremely malevolent, destroying and killing everything. The God of All Creation, in anger, decided to kill the evil God. To accomplish this, He created the world, humans, and six additional Gods: the Fire Goddess, Water God, Earth God, Wind Goddess, and the two strongest Gods, the Light Goddess and the Darkness God. The Light Goddess and Darkness God were in love, or so the Darkness God thought, but it was a betrayal.
One day, the four Gods appeared, floating in the air above the Darkness God's castle in his kingdom. The Darkness God asked, "Long time no see?" The four Gods replied, "You evil God, how dare you speak to us like that? Are you looking down on us just because the God of Creation made you slightly stronger than us four?" The Darkness God inquired, "What happened? What's the matter?" They accused him of killing humans for fun and misusing his powers for evil purposes.
The Darkness God protested, "You guys know it's not like that! The Creator made me the strongest to kill the evil God!" Just as he finished speaking, the Light Goddess stabbed him with her strongest attack, the holy sword Excalibur. All the Gods assaulted him with their most powerful skills. The God of Darkness was severely injured but managed to escape. He went to the God of All Creation and recounted everything, asking for healing. However, the God of Creation replied that He couldn't, as He had exhausted His powers creating the Darkness God.
The Darkness God suggested, "In that case, take my skills and powers and create a system of darkness." The God of All Creation agreed and sealed Himself with the Darkness God within that system. Finally, He created Labrenth, a realm accessible only to humans.