Well, in these fanfictions, a recurring theme is the conflict between Natsu's human side and his dragon side. His dragon spirit gives him great power but also comes with its own set of challenges. Some fanfictions focus on how he balances these two aspects of himself. There's also the theme of self - discovery, as Natsu learns more about his dragon spirit, he also learns more about who he really is as a person.
One popular 'natsu is a dragon spirit' fanfiction might be 'Natsu's Dragon Spirit Awakening'. It delves into Natsu's journey as he discovers more about his dragon spirit powers. It has great character development and exciting plot twists.
One possible fanfiction could involve Natsu forming a unique bond with the Celestial Spirit Draco. Maybe Draco helps Natsu in a battle against a powerful dark mage. In this story, Draco's celestial powers could be combined with Natsu's fire magic for a spectacular display of strength.
It could be a water - based dragon. In that case, Natsu might have some water - related magic in addition to his fire magic. This would make him a very unique character as he would be able to combine two opposing elements in a way that no one else in the Fairy Tail guild could.
In this fanfiction scenario, Draco might be a key to unlocking a hidden power within Natsu. As they interact, Draco reveals ancient knowledge about the origin of Natsu's magic. This knowledge not only helps Natsu become stronger but also deepens their connection. The story could also involve other Fairy Tail members being skeptical of Draco at first, but then seeing his value as he aids Natsu in various battles.
Gray might show up too. He could start as a bit of a rival, not believing that Natsu can really achieve great things with this Dragon God training. But as the story progresses, he could become more of a supporter. And then there's Lucy. She might be worried about Natsu during the training, and also use her celestial spirit magic to help Natsu in some unexpected ways during his training, like summoning spirits that can provide unique challenges for Natsu to overcome.
Potentially, we could see some celestial dragon characters. They might be ancient and powerful beings. Some could be friendly towards Natsu, seeing him as a new hope for their kind. Others might be more hostile, seeing him as an intruder or a threat to their traditional ways. There could also be other mages from different guilds who are either curious or envious of Natsu's situation with the celestial dragons.
Happy, Natsu's flying cat companion, would definitely be a main character. He would be there to provide comic relief as always, but also be a source of emotional support for Natsu during his transformation into a dragon god. Erza might also be a prominent character. With her strong leadership skills and powerful magic, she could be guiding the guild during the times when Natsu is still coming to terms with his powers and the changes it brings to the guild.
In the 'king of dragon slayer fanfiction', Natsu is likely a central figure. He might have special powers related to slaying dragons, like breathing fire or having enhanced strength. His character could be developed in ways that are different from the original series, perhaps with new relationships and challenges within the fanfiction world.
A popular one is 'Dragon's Love for the Celestial Mage'. This fanfiction takes their relationship to a new level. It starts with a simple adventure but soon unfolds into a story of deep love and loyalty. The author does a great job of portraying Natsu's dragon - like instincts when it comes to protecting Lucy, and Lucy's growing feelings for Natsu are also well - written.