Inuyasha's character would lose some of his charm. As a full demon, he would no longer have the endearing qualities that came from his human half. His sense of humor might disappear. He would be more focused on survival of the fittest in the demon world. His loyalty to his friends would be tested as his new demon nature might not value the same things. His character would become more one - dimensional in a sense, as the complexity of his half - demon state is removed. Instead of having the internal struggle that made him interesting, he would just be a full - fledged demon with all the typical demon traits like aggression and a thirst for power.
Inuyasha might develop more self - control. If he has new powers from becoming this 'demon', he would need to control his impulses to use them recklessly. His character could become more introspective as he tries to understand what has happened to him and how to reverse it if possible.
He might lose his connection with his human friends. As a full demon, his instincts could become more savage and he might not be able to control his power as well as he did when he was half - demon. His appearance would also change completely, perhaps becoming more fearsome and less recognizable to those who knew him before.
Tanjiro's character development would take a dark turn. He would start from being a pure - hearted demon slayer to a conflicted being. His internal struggle between his human memories and his new demonic desires would be the main focus. For instance, he might remember his promise to his family but be unable to resist the urge to harm others.
His character could become more serious. Since Creepypasta is full of dark and spooky elements, Naruto might lose some of his naivete. He'd be more aware of the potential threats that lurk in the shadows, both in the real ninja world and in the world of his newfound interest.
His character would develop in many ways. Firstly, his physical strength and endurance would skyrocket. He'd be used to Spartan training which is extremely harsh. Emotionally, he might become more reserved as Spartans don't show emotions as openly as ninjas. His relationships would change too. His friends might see him as a different person, but Naruto would still hold onto his core values of protecting his loved ones. He could bring Spartan values like loyalty and courage in a new and extreme way to the ninja world, influencing those around him to be more like Spartans in terms of their fighting spirit and tenacity.
He would become more confident. Having the power to control elements gives him an edge. He would no longer be just a demigod with limited powers but a force to be reckoned with.
Naruto's sense of identity would be challenged. He was known as the hero of Konoha, but as a ronin, he is an outsider. This could make him more introspective. He might question his past actions and beliefs. He could also become more empathetic towards those who have been marginalized in the ninja world, as he now shares a similar experience.
Naruto's character would likely become more solitary as necromancy is not a common or well - liked art. He'd have to hide his new power at first. As he gets more used to it, he might become more brooding and less of the carefree Naruto we know, constantly thinking about the balance between life and death.
His character would become more open - minded. Naruto is already adventurous, but Bakugan would expose him to a completely different kind of world. He would learn new strategies and ways of thinking from Bakugan battles, which would make him a more well - rounded fighter in both ninja and Bakugan battles.
If Naruto becomes the Kyuubi in the fanfiction, his character development would be a wild ride. He'd start as a regular boy with big dreams, but once he becomes the Kyuubi, he has to face a whole new set of challenges. He has to learn to control his new form and power. This might make him more serious and less carefree as he used to be. He also has to deal with how others perceive him now. Some might fear him, some might worship him. All these things would shape his character in different ways, making him more mature and perhaps a bit more jaded.