Obviously, Timmy is the main character. There could also be a wise old fairy who guides Timmy on his journey as a new fairy. Maybe a mischievous fairy friend who gets Timmy into trouble sometimes. And of course, there could be an evil fairy or a dark force that Timmy has to face.
In this fanfiction, Timmy is the central figure. There might be a fairy queen or king who rules over the fairy realm that Timmy enters. There could be fairy siblings who either help or hinder Timmy. Also, there may be some magical creatures like talking animals or enchanted plants that interact with Timmy as he becomes a fairy. For example, a wise owl that gives him advice or a helpful flower that provides him with a special power when he needs it most.
In this fanfiction, perhaps Timmy discovers a magical world of fairies. He might gain fairy powers like the ability to fly or cast spells. Maybe he'll meet other fairy characters and go on adventures with them, exploring enchanted forests and solving magical mysteries.
Percy himself, of course. His friends like Annabeth and Grover would likely be in it too. Maybe there would be some new characters, like a powerful wizard who helps Percy on his path to fame. Or a mysterious stranger who initially opposes Percy but later becomes his ally.
One possible new character could be a young orphan with a hidden talent for ninjutsu. Naruto, having been an orphan himself, takes the kid under his wing. This new character could have a unique power that is related to illusions but in a much more advanced and dangerous way than the normal genjutsu. Another new addition could be a ninja from a rival village who, after seeing Naruto's growth, decides to join him instead of fighting against him. This character could bring with him the knowledge of the rival village's secret ninja strategies.
Timmy's friends' reactions could vary widely. His female friends might be more welcoming and excited to have him as a 'new girl' in their group. They could start inviting him to do girl - only things like slumber parties or shopping. However, some of his male friends who are more set in traditional gender roles might be a bit standoffish at first. But over time, as they see that Timmy is still the same person on the inside, they could come around and accept him in his new form.
There could also be other supporting characters from the original show that might appear in the fanfiction. For instance, Cosmo, Wanda's husband, could show up and add some comical elements to the story. Or Timmy's friends and family might be involved, as they are often affected by Timmy's wishes and the magic that Wanda helps bring to life.
The main characters are obviously Timmy Turner and Vicky Lemon. Timmy is a young boy with fairy godparents, and Vicky is his mean babysitter in the original show. In the fanfiction, they could be portrayed in different lights, such as friends or allies instead of their typical relationship.
Timmy is the main character in Timmy Time Stories. He is a little lamb.
There could be a wise old monster who acts as Percy's mentor. Maybe a female monster who becomes Percy's love interest. And of course, there would likely be some villainous monsters who oppose Percy's new existence and try to harm him.
One possible plot development is that Natsu, as END, could be hunted by various magical organizations who see him as a threat. This would put him on the run and force his Fairy Tail friends to either protect him or try to stop him if they believe he's too dangerous. Another development could be that Natsu discovers new abilities related to END that give him an edge in battles but also come with a cost, like draining his life force or affecting his mental state.
There might be a family member in the story. For example, a mother - figure who has certain expectations of what a 'wife' should be and has to come to terms with Pussyboi's new identity. Also, there could be a mentor - like character who has gone through a similar identity shift and helps Pussyboi understand and adapt to his new role.