Definitely the dragons would be key characters. There could be a powerful dragon queen who takes Percy under her wing, so to speak. She would be a very important figure in Percy's upbringing, teaching him the values and ways of the dragons. And there might be an outcast dragon, shunned by the others, but who bonds with Percy because they both feel like outsiders. Also, some of Percy's original friends from the demigod world, like Annabeth, might make an appearance. She could be initially confused and then intrigued by Percy's new dragon - influenced self.
Obviously, Artemis. She is in charge of the Hunt, and her relationship with Percy would be central to the story. Then there could be Zoe Nightshade. She was a very important member of the Hunt in the original Percy Jackson lore. If Percy is adopted by the Hunt, she would have a big influence on him, either as a mentor or as someone who initially opposes his presence. And the wolf is also crucial. It could be a mysterious figure, maybe a messenger of the Hunt or a guardian of some sort, and it would be involved in Percy's journey every step of the way.
Obviously Percy himself would be the main character. But there could also be sea nymphs like Amphitrite who could play a big role in raising him. Maybe Triton, son of Poseidon, could be a mentor figure to Percy.
Artemis is a must - as the goddess leading the Hunt. Her hunters, especially those like Phoebe, could be main characters. Phoebe could be curious about Percy and his blindness. She might be the one to first approach Percy when he's found. Another character could be Chiron. He could hear about Percy being with the Hunt and come to check on him. He could offer advice to both Percy and the Hunt, based on his vast knowledge of demigods. And then there's the Oracle. It could give some cryptic prophecy related to Percy's new situation with the Hunt, which would add an interesting layer to the story.
One possible plot could be that Percy discovers he has a special connection with dragons. Maybe he finds out that the dragons sense his demigod powers and take him in as one of their own. He then learns dragon - related skills like flying on their backs or using dragon fire in battles against his usual foes in the Percy Jackson universe.
Piper McLean could be a great addition. Since she has some connection to Aphrodite already. She could either help Aphrodite in her plans or try to protect Percy from her. And of course, we could add some minor gods or goddesses like Eros. He could be Aphrodite's little helper in creating chaos with love arrows, which would definitely fit in with the lemon aspect of the fanfiction if it involves some love - related mischief.
Grover could also be a major character. As Percy's best friend, he would probably be involved in trying to stop Percy if he thinks Percy has gone too far. Or, if he sees the corruption in Olympus, he may side with Percy. Grover's connection to nature means he could play an important role in the events that unfold, like using nature spirits to either protect Olympus or aid Percy depending on his stance.
In this fanfiction, Percy Jackson is the main focus. But other characters from the Percy Jackson universe can also play important roles. For example, Chiron, the centaur mentor, could provide guidance on how to deal with the dragons. There may also be a group of demigods who have a special connection to dragons, and together with Percy, they form a sort of team. Each character would bring their own skills and personalities to the story, whether it's combat skills, knowledge of magic, or an understanding of the dragon world.
Grover could also be a main character. He might be at the scene when Percy gets drunk and try to use his nature - related powers to sober Percy up. Grover could also provide some comical relief with his reactions to Percy's drunken state, like his horrified expressions or his attempts to herd Percy like he would a wild animal.
Well, there could be a wise old wizard who discovers Percy. The wizard takes it upon himself to protect Percy from the forces that might be after him because of his mysterious origins. He becomes like a mentor to Percy, teaching him about the magical world and how to control his powers.
A young mermaid named Ariel could be a main character. She could be Percy's friend and help him explore the underwater world. She could teach him how to swim faster and find the best hiding places from the bigger sea creatures.