Perhaps there is also an old hermit who has knowledge about the dragon's past. He could be a guiding figure, providing the dragon and other characters with valuable information and advice, and he would be an important main character in the fanfiction.
The dragon itself is surely one of the main characters. It could be a majestic and powerful being with a unique personality.
There might be a young wizard or sorcerer who befriends the dragon upon its return. This character could play a crucial role in helping the dragon adapt to the new world and its changed circumstances.
Typically, there would be Targaryen descendants. There might be a strong female Targaryen character who is determined to bring her family back to power. And of course, there would be the dragonriders who are crucial to the Targaryen cause.
Obviously, the Dragon King is one of the main characters. There might also be a sidekick or a loyal servant who has been waiting for his return. And perhaps there is a wise old wizard who helps the Dragon King understand the new world he has returned to.
The dragon lord is the central character, of course. But there could be other important ones too. Maybe there's a wizard who helps or hinders his return. And there could be a brave warrior who either teams up with the dragon lord or stands against him. There might also be some characters from the dragon lord's past that are relevant to the story, like an old friend or a former rival.
There might be a new character introduced in the fanfic. This character could be a commoner who has a special connection with the dragon. For example, a shepherd who once saved the dragon when it was a hatchling and now the dragon has returned to repay the kindness. This character then gets involved in the high - stakes politics of Westeros because of their relationship with the dragon. Another main character could be a powerful lord or lady who sees the dragon's return as a threat to their power and will do anything to stop it or control it for their own gain.
It's hard to say without reading it. But it could be the dragons themselves. Maybe there's a powerful dragon king or queen leading the return. There might also be a human character who plays a crucial role, like a dragon rider or a wizard who can communicate with the dragons.
A powerful dark wizard could be the main antagonist. He might be jealous of the dragon rider's powers and the bond with the dragon, and wants to break that bond and steal the rider's powers for himself.
Well, aside from Naruto, there could be characters like Kakashi Hatake. He was Naruto's mentor, and his reaction to Naruto's return would be interesting. Also, characters from other villages might play important roles. For example, Gaara from the Sand Village. His friendship with Naruto could be explored further in this fanfiction, especially in the context of Naruto's return and how it affects their relationship and the relationship between their respective villages.
Obviously, Naruto and Tenten are the main characters. Naruto, the energetic and powerful ninja, and Tenten, the skilled weapon - using kunoichi.
Typically, there would be Targaryen family members as main characters. For example, a strong - willed Targaryen prince or princess. There might also be dragon riders who are closely associated with the Targaryens.
Obviously, the Dark Knight himself, Batman. He's the central figure around which the story revolves.