Well, in such a fanfiction, the dragon might return with a warning. He could have sensed a dark force rising and has come back to prepare Natsu and his friends. The plot could then revolve around them training hard and forming new alliances to face this impending threat. The return of the dragon would be a catalyst for change, not just in Natsu's life but in the whole magical community they are part of. It could also explore how the other characters react to the dragon's return, some with awe and some with suspicion.
A possible plot could be that the dragon returns after being lost in another dimension. When he comes back, he has new powers and knowledge. He starts to train Natsu in these new ways, which makes Natsu a much more powerful wizard. However, this new power also attracts unwanted attention from powerful and evil forces. So, the story could be about Natsu and his foster father dragon fighting off these new threats while also exploring the newfound relationship between them due to the dragon's long absence and new capabilities.
The plot could be that the dragon's return disrupts the current peace in Natsu's world. Maybe the dragon has some unfinished business with an old enemy, and now that he's back, he drags Natsu into it. Natsu, being loyal to his foster father, follows him into this new conflict. This could involve a lot of action - packed battles and some emotional moments as Natsu has to deal with the potential danger to his foster father.
In a fanfiction about the return of Natsu's foster father dragon, perhaps the dragon returns with a mission. He might have learned of a great threat during his time away and has come back to enlist Natsu's help. This could involve traveling to new and dangerous lands, encountering unique magical creatures, and Natsu having to prove himself once again to his foster father. The story could explore their relationship, which may have some strain due to the long separation.
One possible plot could be that Natsu returns with newfound powers. He might use these powers to help rebuild the world after the war, and also to reunite with his friends. Maybe he has to face some remnants of the enemy forces that still lurk in the shadows.
Maybe Natsu comes back with new powers. He might have to face old enemies that have grown stronger in his absence. Also, his relationships with his friends could have changed, and he'd have to work on rebuilding those bonds.
The fanfiction could start with Natsu's grand return. His friends are overjoyed but soon realize he's different. He might be haunted by the memories of the war. Maybe he lost some dear friends during the war and is now more determined to protect the ones he still has. His return could also trigger some rivalries. There could be those who are jealous of the newfound respect he has earned from the war, or those who think he has become too powerful and might be a threat. This would create a lot of drama and new storylines in the fanfiction.
In some fanfictions, Acnologia is made out to be Natsu's father. But this is not part of the original canon of the Fairy Tail series. Fanfiction writers often like to create such unexpected family relationships to add new twists to the story.
Foster father was a term that referred to a man who adopted another person's child as his own. In literary works, adoptive father could also refer to the characters in the story. For example, the original work "Foster Father" told the story of a mercenary Shan Ming who met a pure-blooded dragon-blooded man, Shen Changze, in the primeval forest and became his adoptive father. This film was full of action, emotions, and boat scenes. The ending was He (a happy ending), and there was also a double couple (a double couple). It was a novel worth watching. In addition, there was also a TV series,"Foster Father," directed by Zhang Guoli. It told the story of the roast duck chef Lou Zhijun adopting three children. This drama showed Lou Zhijun's fatherly love, the children's filial piety, and their emotional growth in illness and separation.
Well, in many such fanfictions, it often involves Natsu and Lucy having a special connection related to dragons. Maybe Natsu's dragon powers play a role in bringing them closer in a romantic or fated - mates - like way. For example, they might go on adventures together where Natsu's dragon instincts protect Lucy in a more profound way than in the original story, and their relationship deepens as they face various challenges side by side.
Maybe Natsu discovers a new magic spell that accidentally turns him into a dragon. He then has to figure out how to reverse it while dealing with the new powers and instincts.
Well, it could be about Natsu having some sort of special connection to the celestial dragons. Maybe he discovers he has celestial dragon blood in him and has to deal with the powers and responsibilities that come with it. He might also encounter other characters who either fear or revere him because of this newfound aspect of his identity.
Well, perhaps it could be about Natsu having some special powers right from birth that are related to dragons. Maybe he can communicate with dragons in a unique way that no one else can since he was born with this dragon - like essence.