December 16, 784, Tenrou Island.

Having defeated Grimoire Heart earlier the same day, the members of the Fairy Tail guild who are currently on the island are now holding hands with each other, waiting for their deaths at the hands of the Dragon King Acnologia who showed up moments ago, knowing that they can not escape its breath attack.

Before the breath attack manages to hit the island and kill off all members, Mavis Vermillion uses a spell known as Fairy Sphere on them, which converts the Fairy Tail members' bonds and faith into Magic Power. The spell also acts as a stasis chamber, a place in which time stops, thus almost everyone within the sphere is stuck in a frozen state in which they don't age, except for Natsu that is. Due to the spell being of holy origin in nature, protecting them from all evil, and Natsu's life being tied to the book of E.N.D., in addition to Natsu being a demon, the spell also blocks off all connection with him and the book as long as the spell lasts, which according to their bonds is around 7 years, meaning that Natsu dies.

Natsu wakes up and sees that he is in a white void of some sort, being face to face with an old man with long white beard, who is dressed in white robes.

"Hello Natsu Dragneel. I have been waiting for you." says the old man with a kind voice.

"Am I dead?" asks Natsu, looking around the place "Who are you? Where are the others?"

"Straight to the point I see." chuckles the old man "I am who is known as the Prime God, the omniscient god who has created all the known dimensions in the multiverse, and yes, you are indeed dead. As for the others, the first master of Fairy Tail named as Mavis Vermillion managed to save them using a spell known as Fairy Sphere, which converts the guild members' bonds and faith into Magic Power, except for you that is, due to your life being connected to a book of Zeref before your death and you being a demon."

"What!" shouts Natsu "I know that I destroy things but I am no demon. Also, what do you mean that my life was connected to a book of Zeref?"

The god then sighs and proceeds to explain to him about his past with his brother Zeref and being resurrected by him as a demon, while Natsu listens to him.

"So let me get this straight. My brother brought me back to life as a demon, and due to the spell, the connection with the book was severed, and due to that I have now died, unlike my friends who are still alive?" asks Natsu "What happens to me now?"

The god strokes his beard with his hand while in deep thought, knowing that Natsu is likely still needed in this world to save the world from certain destruction at the hands of Zeref and Acnologia, and then comes up with an idea.

"How about I reincarnate you?" asks the god "However due to your soul being that of a fire demon, you will no longer be a human in your next life. I will also make it so that you will remember your past life as Natsu Dragneel when you have became of certain age. After you reach the age you are now, I will return you to this world as you are still needed to save this world from certain destruction."

"Really!" cheers Natsu, and asks "I can return back to this world and see my friends?"

"Yes." confirms god, bringing a smile to Natsu's face.

"Then what are you waiting for." says Natsu, his face being full of happiness "Reincarnate me!"

The god then snaps his finger and Natsu vanishes from the dimension.

In the Phenex estate, Lady Raylia Phenex has just given birth to twins. Two boys with blonde hair and blue eyes. The older twin was named by her husband, who he decided to name as Riser Phenex, while the younger was named by her, who she named as Natsu Phenex, not knowing why she did, as her husband let her break family tradition and pick a suitable name herself.

Once Natsu Phenex reached the age of 7, he started to have vivid dreams of another life in a different world, which greatly worried his parents. The dreams also influenced his personality and stopped when he was around 15 years old. As a result of his dreams, Natsu no longer knew whether he is Natsu Phenex or Natsu Dragneel, but he knew that he had friends in another dimension who he wishes to meet again due to having successfully learned Fire Dragon Slayer magic in this life also, while his idiot twin brother Riser Phenex was unable to do so.

Natsu Phenex now is the same age as he was when Natsu Dragneel died. He is stronger than he was while in Earthland and has inherited the abilities of the Phenex clan in addition to Fire Dragon Slayer Magic.

As most of the Phenex family are sitting in the living room, the old man known as Prime God appears in front of the shocked Phenex family.

"Hello, Natsu." says the Prime God "We meet again after all this time."

"Who are you?" asks Lord Ravolo Phenex, despite having heard from him from Natsu in the past.

"I am who is known as the Prime God and I have come in order to fulfill my promise to Natsu Dragneel to bring him back to Earthland."

'So it is all true then?' were the collective thoughts of the Phenex family.

"Say your goodbyes to your family for the time being." says the god "I will return you back once you have saved Earthland from both Zeref and Acnologia."

Ravel quickly runs up to Natsu.

"Don't go brother!" cries Ravel Phenex, holding Natsu's shirt.

"Don't cry Ravel." replies Natsu, wiping away her tears "If what he says is true, than I will someday return. For now stay strong and become a good little sister for me, ok?"

His parents who know how Natsu misses seeing his friends on Earthland smile at him.

"Then, take care my son." says his father "Show them the might of the Phenex clan."

"Once you return, do bring home some girls with you, Natsu." teases his mother, hoping that her son will finally get himself some Peerage members.

The god then snaps his fingers and Natsu returns to Earthland.

In Tenrou Island, the dead body of a pink haired, black eyed Natsu Dragneel is replaced with a blonde haired, blue eyed sleeping Natsu Phenex, while Mavis Vermillion leads the Fairy Tail rescue party to Tenrou Island, not knowing that Natsu is once again back among the living.

Authors notes:

Natsu has no Peerage members, but has his own set of Evil Pieces. He will return to the DxD world after the events in Fairy Tail world have ended. Prime God knew that Natsu will die the moment Mavis used the spell but decided against saving Natsu as this way Natsu will be stronger than canon and his life will not be tied to a book as he saw a bad ending for Natsu in his original timeline.