One possible fanfic could be about a student of Orochimaru who rebels against his evil ways. This student, perhaps having seen the destruction Orochimaru causes, decides to use the knowledge he has gained in a positive way. He might start by secretly helping the Hidden Leaf Village, using his skills in jutsu and forbidden arts to protect rather than harm.
The student could go on an adventure to find a cure for Orochimaru's curse mark. Since Orochimaru often experiments with curse marks on his students, this one particular student might be determined to find a way to get rid of it once and for all. He could travel to different hidden villages, seeking out ancient scrolls and wise sages for answers.
One possible fanfic could be about a student of Orochimaru who struggles with the dark arts they are being taught. This student might start to question Orochimaru's motives as they see the harm his experiments cause. For example, they could witness the pain of the test subjects in Orochimaru's lair and decide to rebel. They might try to find a way to use the knowledge they've gained for good, like developing healing jutsu based on Orochimaru's research on the human body.
In some fanfics, Naruto might use his new and powerful jutsu that he has mastered over time. Maybe he combines his Sage Mode with the power of the Nine - Tails in a unique way that Orochimaru can't counter. For example, he could use the Nine - Tails' chakra to enhance the range and power of his Sage Mode attacks, and then catch Orochimaru off - guard.
Another aspect could be the student's struggle to adapt to the ninja world while being in Orochimaru's territory. They would have to learn ninja skills quickly. Since they are an OC (original character), they might have some unique abilities from their past life that could either help or hinder them. For instance, if they were a science whiz in their previous life, they could try to introduce new scientific concepts to Orochimaru's lair, which might earn them respect or suspicion.
Perhaps the fanfic could be about an Orochimaru's student who is sent on a secret mission. On this mission, they meet different characters who make them question their loyalty to Orochimaru. They could also find a hidden power within themselves that is not related to Orochimaru's teachings. This new power could be the key to their redemption or a new path away from Orochimaru.
One consequence could be a shift in the power balance among the ninja villages. Since Orochimaru was a powerful and feared figure, his death might cause some chaos as his former allies or subordinates try to either avenge him or claim his resources. For example, some of his secret labs and experiments might be up for grabs, leading to potential conflicts.
In fanfic, anything can be possible, so Orochimaru could be Naruto's father. But in the official Naruto storyline, it's not the case. Naruto's parentage is clearly defined as Minato and Kushina. Fanfic writers might be trying to explore a different kind of family drama or a new take on the characters' relationships by creating this unorthodox connection.
In some fanfics, Orochimaru can be made Naruto's sensei. Fanfic authors often like to play with the original story's elements and create unique scenarios. They might think that having Orochimaru as Naruto's sensei would lead to a very different kind of character development for Naruto, full of more moral and ethical challenges due to Orochimaru's dark nature.
Naruto might resist through his strong willpower. He has always been determined, and this would not change even under torture. He could keep thinking about his friends in the Leaf Village and his goal of becoming Hokage, which gives him the strength to endure.