Characters like Sakura and the other members of Team 7 could also be main characters. Sakura might be involved in helping Naruto with his new powers, perhaps using her medical ninjutsu knowledge. And the other members of Team 7 would contribute to the story through their unique skills and relationships with Naruto.
Obviously, Naruto is one of the main characters as the story is centered around him being the son of six paths. Sasuke could also be a main character as he has always been Naruto's rival and friend. Their relationship would likely be further explored in this fanfiction.
The Six Paths Sage himself could potentially be a main character, either in flashbacks or as a guiding spirit for Naruto. His wisdom and power would play a significant role in Naruto's development. Also, Kakashi could be there as Naruto's former teacher, providing guidance and support as Naruto navigates his new identity.
In this fanfiction, Naruto is bound to be a main character. Alongside him, there could be antagonists who are interested in the power of the Six Paths Senjutsu for their own evil purposes. These could be new villains or old foes with a new motivation. Also, characters like Jiraiya might make an appearance, either through flashbacks or some sort of spiritual guidance, as he was Naruto's mentor and had knowledge about various ninja arts, which could be related to the Six Paths Senjutsu in some way.
Sasuke is often involved too. In many fanfictions, his rivalry with Naruto takes on a new dimension when the Six Paths power comes into play. He might either be jealous of Naruto's new power or try to find a way to equal it on his own.
Obviously, Naruto is the main character since it's about him being the Sage of Six Paths. But other characters like Sasuke are often important too. Sasuke might be Naruto's ally or sometimes a rival even with Naruto's new status.
Hinata could also be a main character. Her relationship with Naruto could take on new dimensions as he becomes the Sage of Six Paths. Maybe she helps him in some way to control or understand his new powers, or they face challenges together that test their relationship.
Maybe an ancient demon that was once sealed by the Sage of the Six Paths but has now been released. This demon could be bent on revenge and see Naruto, as the inheritor of the Sage's power, as its main target. It would be a formidable foe, with abilities that could test Naruto's new - found powers and his resolve. The demon could also corrupt other ninjas to do its bidding, creating more chaos in the ninja world.
Another plotline could be centered around Naruto's relationships. His friends and allies might react differently to his new status. Some might be in awe, while others might be a bit jealous or worried. This could create some interesting dynamics and conflicts within the story.
Obviously Naruto and the Sage of Six Paths. Naruto is the main protagonist of the Naruto series, so it's natural for him to be a main character in this fanfic. And the Sage of Six Paths is a very important figure, so his presence is crucial.
There could be some ancient ninja spirits that the Sage of Six Paths summons to help Naruto train. They might have unique powers and fighting styles.
Well, it could be that the main characters are not just the trio from the original Harry Potter books. It might introduce new characters who are specifically created for this fanfiction to better fit the Six Paths of Pain theme. However, if it follows the original story closely, it's likely that Harry Potter would be a main character, with Voldemort perhaps being another important figure as the source of the 'pain' in some way. And there could be other characters like Dumbledore who might play a role in guiding the characters through the six paths of pain, whether it's helping them understand or resist the power related to it.
In this fanfiction, the main antagonists could be a secret organization that has been studying the Six Paths powers in the shadows. They see Naruto as a threat to their plans of world domination. They could have their own powerful members with unique abilities that are specifically designed to counter Naruto's newfound powers as the Sage of the Six Paths. They might try to manipulate events and turn Naruto's friends against him to weaken his position.