Another potential character could be a rival from a magic - using clan. This rival might be jealous of Naruto's newfound powers and constantly try to outdo him. There could also be a magical guardian spirit that has been protecting Naruto's family's magic for generations. It appears to Naruto when he's in great danger and helps him harness his magic powers more effectively.
Perhaps there's a group of magic - wielding ninjas who are either friends or foes. They could have different types of magic, like earth - magic ninjas or wind - magic ninjas. And there might be a powerful sorceress who has a connection to Naruto's family and she could play a key role in his journey to understand his magic.
There could be characters related to Luna. Maybe Luna has some friends or family members who play important roles. Also, the regular Naruto characters like Sasuke and Sakura would still be there, but their relationships with Naruto might change due to his new identity as Luna's son.
Sakura could be one. She has a long - standing relationship with Naruto and might be part of the harem. Also, Hinata. Given her feelings for Naruto, she could be drawn into this situation. Shikamaru might also be included, not in a romantic way for Naruto but as a friend who gets involved in the group dynamic. And Kiba, with his brash personality, could add an interesting element to the group.
Princess Luna herself would be an important character. Also, characters like Sasuke could be there, and their relationship with Naruto might change because of his new heritage.
Obviously, there would be the queen vampire, his mother. She could be a powerful and mysterious figure, perhaps with her own motives and plans for Naruto. There might also be some vampire elders or nobles who play a role in Naruto's life, either guiding him or trying to use him for their own purposes.
Kakashi could also play a major role. He has a wealth of knowledge and experience, and could guide the son in his training. And then there's Tsunade. As the Hokage, she might be involved in decisions regarding the son's presence in the village and could also offer her medical expertise when the son gets injured during his adventures. There could also be some of the tailed beasts as characters, as they have their own powers and could interact with the son in various ways.
Sasuke could be a great choice. He has that brooding, anti - hero vibe that could fit well in the criminal underworld. Maybe he gets drawn into the crime boss's schemes because he thinks it's a way to gain more power to achieve his own goals.
One character could be Jiraiya. He could have known something about Naruto's true heritage all along and be the one to finally reveal it to Naruto. From the Greek side, Triton, Poseidon's son in mythology, could be a character. He could either be a rival or an ally to Naruto. In the ninja world, Shikamaru might be involved. His intelligence could be used to help Naruto understand and strategize with his new powers, especially when dealing with any threats that come his way because of his connection to Poseidon.
Obviously Naruto as the main character. Sasuke could be there, and his relationship with Naruto might change due to Naruto's new identity. There could also be characters from the underworld, like minions of Hades or other mythological creatures.
Obviously Naruto himself. There could also be the other Naruto characters like Sasuke, Sakura, and Kakashi. And perhaps some Egyptian god - like characters related to Anubis, like his servants or other gods who interact with Naruto due to his relation to Anubis.
Obviously Naruto himself. Then there could be Athena, who might appear in some form, either as a guiding spirit or in flashbacks. His friends like Sasuke and Sakura would also be there. Maybe some Greek mythological characters like Hermes could show up to interact with Naruto, since he is now related to their world.