It could be a new character created specifically for the fanfiction. Maybe a young ninja who discovers their relation to Hagoromo later in life.
It might also be an existing character who is revealed to be a descendant. For example, Naruto himself could be further explored as having a closer connection to Hagoromo than previously thought. This would add a new layer to his character and his already amazing powers.
Well, it could be about the main character having special powers inherited from Hagoromo. Maybe they have to face new threats that only someone with Hagoromo's blood can handle.
Perhaps it could be another entity related to Hagoromo. If Naruto abandons Hagoromo, there might be a counterpart or a follower of Hagoromo who sees Naruto as a threat or a traitor. This person could then become the main antagonist, trying to either bring Naruto back to Hagoromo's side or simply eliminate him.
It could be Naruto himself. Imagine if Naruto was secretly a descendant of Sparda. He would already have his own powerful chakra and then add the powers from Sparda's bloodline. It would make him an even more formidable force in the ninja world.
Perhaps it could be an existing Naruto character like Naruto himself, but in an alternate universe where he has this Nero connection. This would change his character arc quite a bit as he has to deal with this new aspect of his identity. He might have to learn new skills or face different types of enemies due to his Nero descendant status.
It could be Naruto himself. Imagine if through some magical or mysterious event, Naruto was revealed to be a descendant of Hiei. His already strong will and determination could be enhanced by Hiei's traits, making him an even more formidable ninja.
It could be a new character who is introduced as the descendant. Maybe a young ninja who has always felt a bit different from the others in their village. They start to have strange dreams related to Alice and then begin to uncover their unique heritage.
It might be Naruto's long - lost relative. This would add an interesting twist as Naruto is already a very powerful and well - known character. His relative having Frieza - like powers would create a lot of drama and new storylines. For example, Naruto might have to help this relative control their powers or deal with the consequences of having such a unique heritage.
The main character could be an existing Naruto character who somehow discovers they have Sesshomaru's bloodline. For instance, Naruto himself could be the one. Imagine if during one of his adventures, he unlocks a hidden power within him that is related to Sesshomaru. This would completely change his dynamic and how he approaches battles and relationships in the ninja world. He would have to learn to control new powers like Sesshomaru's poison claws or something similar.
It could be a powerful ninja who has become corrupted by the idea of the descendant's powers. He wants to steal those powers for himself to gain ultimate control over the ninja world. Maybe he has a deep - seated envy of the unique combination of abilities the descendant has.
It could be a rogue ninja who wants to use the descendant for their own power - gain. Maybe someone who believes that by controlling the descendant, they can access Kaguya's ultimate power. For example, a power - hungry ninja who has been researching Kaguya's secrets for a long time.