Well, Orochimaru's immortality would mean that his influence would be long - lasting. He could continue to conduct his unethical experiments over a very long period. This might lead to the creation of new and dangerous ninja techniques or even new forms of life. In the long run, it could change the way ninja are trained and how the ninja world views power and knowledge. For example, some might start to see immortality as the ultimate form of power and strive for it at all costs. Naruto and his friends would have to constantly be on guard against Orochimaru's schemes.
It would likely strain his relationship with Sasuke. Sasuke has his own complex history with Orochimaru, and if Naruto becomes a fan, Sasuke would be very confused and probably angry. He might see Naruto as betraying their shared values. As for his friends in Konoha, they would also be worried and try to talk Naruto out of it, which could lead to some arguments and a rift in their friendships.
The story would also change in terms of Naruto's relationships. His friends like Sasuke and Sakura would be very concerned and might try to stop him. This could lead to a rift between them. Naruto might gain new powers faster, but at a cost. He could start to lose his connection to his normal self and the Nine - Tails inside him might react negatively to the experiment.
It changes the Naruto universe in several ways. Firstly, Fem Orochimaru's actions would be different from the male Orochimaru's. Her motives for taking Naruto might not be as purely power - hungry. This could lead to different alliances and enmities. For example, some characters who were against Orochimaru might be more lenient towards Fem Orochimaru if she shows a more benevolent side. Secondly, Naruto's growth and development would be altered. Instead of following the path with Jiraiya, he's with Fem Orochimaru. So his jutsu and combat style might incorporate more of her unorthodox and perhaps more feminine - influenced techniques. Also, the perception of Orochimaru's lair or hideouts would change. It could be less of a spooky, evil - filled place and more of a place of mystery and potential redemption.
It could have a major impact on the power balance. With Orochimaru gone, many of his secret experiments and knowledge could be lost or fall into the wrong hands. Naruto, being 'godlike', might be seen as the new power to keep in check. His friends and allies might start to distance themselves out of fear or respect for his new power level. The Akatsuki, too, would need to re - evaluate their plans as one of their potential allies or threats (depending on Orochimaru's relationship with them at the time) is no longer in the picture.
In this fanfiction, their relationship could be full of tension. Orochimaru is a character who often pursues power through unorthodox means. Naruto, on the other hand, values life and friendship. So, they would constantly be at odds. But at the same time, there would be a sense of loyalty between them as brothers. Orochimaru might try to manipulate Naruto at times, while Naruto would be trying to redeem his brother, leading to a very tumultuous relationship.
Sakura would be worried sick. She might immediately inform Kakashi sensei and the rest of the village. Then, she would probably want to be part of the rescue mission. Sakura has grown stronger over time and would use her medical ninjutsu and combat skills to help save Naruto. She would also be constantly worried about Naruto's well - being and would encourage the others to move faster.
Naruto would likely become more secretive. Since Orochimaru is a very private and often devious character, Naruto might pick up some of those traits. He would probably keep things from his friends more often.
Naruto's character development in this fanfiction would be complex. He'd probably grow up with a sense of superiority due to Orochimaru's powerful teachings. But at the same time, he'd lack the warmth and compassion that came from his relationships in Konoha. He might be more self - centered, focused on his own power and survival. He may not have the same sense of justice as in the original Naruto, as Orochimaru's motives are not in line with the general good. And his relationship with his peers would be more of a power struggle. He might not form the same deep friendships, but rather see others as either tools or threats.
Naruto's character would likely become more conflicted. He has always been on the side of good, and joining Orochimaru, even if for a good reason, would put him in a morally gray area. His view of power might change as he is exposed to Orochimaru's unorthodox ways of obtaining it.
In some fanfictions, Orochimaru might develop a sense of loyalty towards Naruto. After being around Naruto for a while, he could see Naruto as someone worthy of his loyalty. This could lead to him being more open to working with the Hidden Leaf and helping Naruto in his various missions. He might even sacrifice his own interests to protect Naruto at times, which is a complete turnaround from his initial character.