One possibility could be that Naruto starts taking better care of himself. Maybe he learns some new jutsu that has an unexpected side effect of enhancing his appearance. For example, a jutsu that purifies his chakra more effectively also clears up his skin and gives him a healthy glow.
Perhaps in the fanfic, Naruto travels to a different land where they have unique beauty practices. He gets involved in their rituals and uses some special herbs or techniques that gradually change his appearance for the better. He comes back to Konoha looking much more handsome and all his friends are quite surprised.
One possible plotline could be that Naruto discovers a new jutsu that not only enhances his power but also changes his appearance. This jutsu might have some unforeseen side effects that gradually make him more and more handsome. For example, it could be related to chakra control and as he masters it better, his physical features start to change in a more appealing way. Maybe his hair becomes shinier, his eyes more piercing, and his face more chiseled.
A possible plot is that Naruto accidentally drinks a magic potion created by an eccentric inventor. This potion makes him handsome but also gives him some strange powers related to charm. He has to learn to control these new powers while dealing with the attention he gets from everyone, including some unwanted attention from villains who want to use his new charm for their own evil purposes. In the end, he figures out how to reverse the potion but decides to keep some of the confidence his new looks gave him.
If Naruto lost all his friends in a tragic way, perhaps in a large - scale attack on the village where he couldn't save them despite his best efforts. The grief and guilt could consume him and change his values. He might start to think that the shinobi world is cruel and needs to be changed by force, which would lead him to become a villain in the fanfic.
There were many novels that told the story of the protagonist turning from an ugly man to a handsome man through hard work and struggle. This kind of plot would usually attract the readers 'interest and motivate them to change themselves for the better. This type of novel often involved love, friendship, growth, and other topics. It was worth reading.
Well, a great plot twist could be that Naruto, as a cat, gets adopted by Sasuke unknowingly. Sasuke then starts to notice some strange things about this cat, like it seems to understand complex ninja concepts when he talks about them. This could lead to some really interesting interactions as Sasuke tries to figure out what's so special about this cat. And maybe Naruto, in cat form, has to protect Sasuke from a new threat without revealing his true identity.
In a fanfic, Naruto and Kurama could become friends when Naruto starts to understand Kurama's pain. Naruto, being the kind - hearted person he is, might try to communicate with Kurama on a deeper level. He could share his own feelings of loneliness and being an outcast in the village at first. This mutual sharing of emotions could break the ice between them and start the process of friendship.
In such a fanfic, they might start by sharing their lonely childhood experiences. Naruto could tell Gaara about being shunned in the village, and Gaara could share his own feelings of being feared. This mutual understanding could lead to them training together, with Naruto teaching Gaara some of his unique jutsu, and Gaara showing Naruto how to better control his chakra in the desert environment.
One possible plot could be that Naruto, in his journey to master his new form as the Kyuubi, seeks guidance from Kurenai. Kurenai, with her knowledge of genjutsu and combat experience, could train Naruto to control the wild power of the Kyuubi within him. This would involve Naruto facing internal struggles as the Kyuubi's instincts clash with his own values. Along the way, they might face common enemies who are interested in Naruto's new power or want to use it for their own evil purposes.
A possible plot is that an ancient scroll is discovered in the Hidden Leaf Village. When Naruto reads it, it unlocks a latent power within him that is related to the Super Saiyan 4 transformation. He starts to have visions of a being with great power who looks like a Super Saiyan 4. As he delves deeper into understanding this new power, he has to train in isolation. His enemies, thinking he's weak during this training period, launch an attack on the village. But Naruto emerges in his Super Saiyan 4 form just in time to save everyone and defeat the villains. This form could also give him new abilities like flying without the use of his shadow clones and enhanced sensory perception.
Well, one possible plot development could be that Naruto starts training intensively with one of the remaining Sannin, like Jiraiya in spirit or Tsunade. He might learn new and powerful jutsus specific to the Sannin's style. For example, he could master Tsunade's super - strength techniques and combine them with his own shadow clone jutsu for some really unique combat moves. Maybe he also gains a deeper understanding of medical ninjutsu, which could be a great addition to his skills set as he often gets injured in battles.