One really engaging plot is when the dragon - turned - human has to learn about human relationships. In a fanfic I read, the dragon - turned - human was completely clueless about friendship and love. He thought that loyalty in the dragon world was the same as in the human world, but he soon learned that human relationships are much more complex. There are also plots where the dragon - turned - human has to prove themselves to the Fairy Tail guild. They are seen as an outsider at first, and they have to show that they are worthy of being part of the guild, which often leads to exciting adventures and battles.
Well, in some fanfics, the plot revolves around the dragon - turned - human bringing a new perspective to the Fairy Tail guild. Since they have a different view of the world as a dragon, they can offer unique solutions to problems. For instance, they might have a better understanding of certain ancient magics because of their dragon heritage. Also, the idea of the dragon - turned - human having a connection to an ancient dragon prophecy is quite interesting. They might be the key to saving the world or preventing a great disaster, which sets them on a grand quest filled with danger and discovery.
One popular 'Fairy Tail dragon turned human' fanfic is 'The Dragon's New Form'. It explores how a dragon, who has been living in its dragon form for centuries, suddenly turns human. The story delves into the character's struggles to adapt to the human world, like understanding human emotions and social norms. It also has great character development for the former - dragon - now - human, as well as for the other Fairy Tail characters who interact with this new being.
There are fanfictions where the Ice Dragon has a connection to a lost realm within the Fairy Tail universe. The main character, perhaps a young mage, has to team up with the Ice Dragon to explore this realm and uncover its secrets. This often leads to all sorts of adventures, battles against strange creatures, and the discovery of new magic. In some plots, the Ice Dragon is actually a reincarnation of an ancient Fairy Tail hero, and the story unfolds as they regain their memories and powers, which is really fascinating.
A really cool plot would be if the Demkn has the power to steal the dragon's magic for a short time. So the dragon has to fight without its main source of power, which makes for a very different and exciting battle. And as the battle progresses, the dragon discovers a new way to use its physical strength and the environment to its advantage. There could also be a plot where the Demkn is a creation of an evil wizard to specifically target dragons. The dragon then has to not only fight the Demkn but also figure out who is behind its creation and stop them before more Demkn are created.
Well, one interesting plot could be the dragon slayers teaming up against an ancient and powerful dragon that was thought to be a myth. They might have to discover new magic powers within themselves to stand a chance.
Wendy Marvell is also a favorite. As a Sky Dragon Slayer, she has a strong connection to dragons. In fanfiction, her growth as a dragon - human or her deeper relationships with dragons are often the focus. Her kind and gentle personality also adds an interesting dynamic to the stories.
One more interesting plot could be that the Fairy Tail guild decides to put on a play based on the story of Jane Eyre. However, as they start rehearsing, the characters start to actually live out the emotions and experiences of the Jane Eyre characters in real life. So, the normally carefree mages of Fairy Tail have to deal with the complex relationships, class differences, and emotional turmoil that are central to Jane Eyre.
One interesting plot could be Naruto having to prove himself in Fairy Tail's guild. Since he's from a different world with different powers, the members might be skeptical. He'd have to show that his ninja skills are just as valuable as their magic. Another plot could be him finding a way to combine his chakra with magic. It would be really cool to see how he uses this new power to fight against common enemies.
A really interesting plot could be Layla's encounter with a long - lost relative who has a different view on magic. This relative might try to convince her to use her magic in a more self - serving way, which would create an internal conflict for Layla as she is a kind - hearted character.
In Fairy Tail fanfics, a really exciting dragon vs demon scenario could be where a dragon has been corrupted by dark magic and turned into a sort of half - dragon half - demon entity. A group of Fairy Tail mages then has to face this powerful being, which has the combined strength of both a dragon and a demon. Another scenario could be a time - traveling demon that goes back in time to try and kill a dragon before it becomes too powerful, but the dragon is aware of the demon's plan and a battle ensues. There could also be a scenario where a dragon and a demon are forced to team up against an even greater evil, but their natural enmity causes constant friction and mini - battles between them during their alliance.
A plot could revolve around Sesshomaru's loss of his demonic powers. As a human, he has to find new ways to protect himself and those he cares about. He could start learning human fighting techniques or rely on his wits more. There could also be a plot where he discovers new aspects of the human world that he was oblivious to as a demon, like art or music, and these new interests change his view of humans and the world in general.