In addition to Lucy and Erza, there could be other female characters from the series. Maybe some minor characters who have always admired Natsu from afar. For example, that one girl from the guild who always blushes when Natsu is around. Another possibility is a powerful female dragon who sees Natsu's transformation into a Dragon God as a sign of his worthiness. She might join his harem, bringing a different kind of relationship dynamic as she has her own dragon - like qualities and power. And there could be a female mage from a different guild who hears about Natsu's new status and is intrigued, eventually becoming part of his harem.
Well, considering the world of the story, there could be a variety of characters in Natsu's harem. There might be a mysterious girl from a far - off land who has a special connection to dragon magic. She senses Natsu's new power and is drawn to him. Also, a young apprentice mage who looks up to Natsu could develop deeper feelings for him as he becomes a Dragon God. And don't forget about any potential female characters from Natsu's past that we haven't seen much of yet. They could reappear and be part of his harem, each with their own backstory and reasons for being attracted to Natsu.
Well, it could be about Natsu's journey to becoming a Dragon God and how he attracts a harem along the way. Maybe he gains new powers that make him irresistible to certain characters.
There could be a female dragon named Ignis who is very fiery and passionate, always trying to be the closest to Natsu. Another could be a more gentle dragon named Aqua, who has water - based powers and uses her calm nature to balance out the more intense dragons in the harem.
Well, it could be about Natsu suddenly finding himself in a situation where he has multiple dragon companions who are all attracted to him. Maybe he has to deal with their different personalities and powers while also trying to figure out how he got into this harem situation in the first place.
Lucy could be a likely member. She has a close relationship with Natsu already in the original story. Another one could be Erza. Her strong and independent nature might be attracted to Natsu's new godlike power. And Wendy, being young and impressionable, might also be part of the harem as she looks up to Natsu.
Well, Mirajane could be part of the harem. She has a motherly side and would want to comfort Natsu if he was betrayed. Levy is also smart and resourceful, and she could use her skills to help Natsu out. Juvia, with her obsessive love for Gray, might transfer some of that intense loyalty to Natsu if she saw him in a desperate situation after being betrayed.
Well, obviously Lucy from Fairy Tail would be a likely candidate. She already has a strong connection with Natsu in the original series. Then from the world of Bleach, Rukia could be an interesting addition. Her cool and collected nature would contrast with Natsu's hot - headedness, and her Soul Reaper powers would add an interesting dynamic to the harem. Also, from Attack on Titan, Mikasa could be in the harem. Her strong combat skills and protective nature towards Eren could translate into a similar protectiveness towards Natsu in the fanfiction.
Maybe an ancient dragon that has been awakened from its slumber and views Natsu as an intruder in the dragon world. Since Natsu is a new - made dragon, this old dragon might try to drive him out or even harm him.
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.
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.
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.