One possible reason could be that Naruto feels he has learned all he can from Jiraiya at that point. Maybe he has reached a level in his training where he believes he needs new experiences and challenges that Jiraiya can no longer provide.
Jiraiya's reaction might be complex. He might be in awe of Naruto's new power but also sad about his departure. He could see it as a natural progression in Naruto's journey, yet still feel a pang of loneliness. He might start to reflect on his own life and training methods, wondering if he could have done something differently to keep Naruto with him. At the same time, he would be eager to see what Naruto will achieve in the world with his newfound abilities.
One possible reason could be that Naruto feels he has learned all he can from Jiraiya at that point. Maybe he wants to explore his own path independently and test his skills without Jiraiya's constant guidance.
It can create a sense of growth for Naruto. Without Jiraiya by his side, he has to rely more on his own instincts and the skills he has already acquired. This can lead to new character development as he faces challenges alone.
They might have adventures in training Naruto to control the Nine - Tails' chakra better. Jiraiya could take Naruto to different secluded places where he can practice without distractions. Maybe they encounter strange and powerful beasts along the way, which Naruto has to learn to fight using his new skills.
One possible plot could be that Naruto, having achieved a god - like state of power, feels he has outgrown Jiraiya's teachings. He might leave to explore new realms of power on his own. He could be on a quest to face threats that Jiraiya no longer has the ability to help him with, and he wants to protect the village in a way that goes beyond what Jiraiya has shown him.
It can change Naruto's character development significantly. Without Jiraiya's direct influence, Naruto might have to rely more on his own instincts and the knowledge he has already acquired. This could lead to a more independent and self - reliant Naruto.
Naruto's character develops through the training he receives from Jiraiya. He becomes more disciplined. For example, he learns to wake up early every day for training without complaining like he used to in Konoha. His ninja skills also improve, which boosts his confidence.
One possible scenario could be that Naruto leaves to train in isolation. He might feel that he needs to become stronger on his own without the guidance of Jiraiya, and so he sets off to find new ways to improve his skills.
His character may become more withdrawn at first. Losing Jiraiya, who was like a father figure to him, could make Naruto less open and more focused on his internal pain.