Perhaps he is influenced by someone he admires who has red hair. It could be that he saw someone with red hair doing something really cool and he wanted to emulate them in some way, starting with the hair color.
Maybe he just wants a new look. Naruto is always known for his wild and adventurous spirit, so dyeing his hair red could be a way to show his rebellious side or simply to stand out more.
It could be related to a specific event in the fanfic. For example, if she's going undercover for some mission, changing her hair color might be part of her disguise. Also, perhaps she's influenced by someone she admires and decides to copy their hair color.
Shikamaru might just sigh and say something like 'What a troublesome thing to do, Naruto.' But deep down, he would also be a bit curious about why Naruto decided to dye his hair red.
Perhaps it's a genetic thing that gets triggered later in life. In some fanfictions, Naruto's family history could be rewritten or expanded. There might be some hidden genetic trait from an ancestor that suddenly surfaces, causing his hair to turn red. This could also be linked to a new power or ability that he has to learn to control as his appearance changes.
One possible reason could be a plot by an enemy to undermine Naruto's legacy. By taking the heir name, they can create confusion and disrupt the line of succession in Konoha. It might also be part of a political maneuver within the village, where some faction wants to gain control over Naruto's influence through his heir's name.
One possible reason could be some sort of new chakra transformation. Maybe he taps into a different power source that affects his physical appearance, including his hair color. For example, if he were to inherit a special kekkei genkai from an unknown lineage that has the side - effect of changing hair color when activated.
It could be a misunderstanding. Perhaps Naruto was involved in an incident where his actions were misinterpreted by his brother. For example, Naruto might have accidentally caused harm to someone his brother cared about while trying to do something good, and his brother didn't get the full story and started to hate him as a result.
One possible storyline could be that Naruto meets a red - haired character who has a special ability related to fire. They team up on a mission and Naruto gradually develops feelings for this character because of their courage and unique skills. The red - haired character might also be from a different village, which adds an element of intrigue to their relationship.
Well, perhaps it's a sign of his connection to a new, mysterious entity. For example, he might have made a pact with a powerful ice - based spirit or demon, and as a result, his hair turned white like snow. Or it could be due to a powerful transformation that was caused by a unique combination of his Uzumaki and Namikaze bloodlines. In the world of fanfiction, there are countless ways to explain such a change, and this is just the tip of the iceberg.
It could be due to a genetic mutation in the Naruto universe. In some fanfictions, there might be a hidden genetic factor in his family line that gets activated. For example, perhaps Minato or Kushina had a recessive gene for white hair that Naruto inherits and it suddenly shows up under certain circumstances, like extreme stress or a coming - of - age moment in his ninja journey.
One possible motive could be Naruto's extreme sense of loyalty and friendship. He might believe that by sacrificing himself, he can save Sasuke from the darkness completely. He could think that his death would shock Sasuke into realizing the error of his ways and bring him back to the side of good.