Perhaps Naruto starts to have a connection to Orochimaru's other experiments or creations. He might find himself in a situation where he has to either help or fight these other 'products' of Orochimaru's mad science. Also, the fanfiction could explore how Naruto's friends react to what has happened to him. Do they trust him still? Or are they afraid of what Orochimaru might have turned him into?
Well, in such a fanfic, a plotline might involve Naruto's friends trying to rescue him. They could discover Orochimaru's lair where Naruto is being experimented on. Meanwhile, Naruto himself could be developing new and unexpected powers as a result of the experiments, which he then has to learn to control. And there could be a race against time for Naruto's friends to reach him before Orochimaru's experiments cause irreversible damage.
A possible plotline could be Orochimaru's redemption. He realizes the error of his ways and joins Naruto in protecting the ninja world. He could use his vast knowledge of jutsu and forbidden arts to help Naruto against new threats.
He could have physical deformities. Orochimaru's experiments are often extreme and might cause Naruto's body to change in abnormal ways. Also, he might have mental trauma. The experience of being experimented on could leave him with psychological scars that affect his relationships and his ability to trust.
Naruto could develop a new sense of determination. He might be determined to not let Orochimaru's experiments define him. Instead, he could use what has happened as a motivation to become stronger in his own way. He may also start to study more about the type of experiments Orochimaru was doing, not to replicate them, but to find ways to counter any future threats related to that kind of science.
One possible plotline could be Naruto being captured by Orochimaru and forced to endure various genetic experiments. Maybe Orochimaru is trying to extract the power of the Nine - Tails from Naruto in a more invasive way. Another could be that Naruto's friends, like Sasuke and Sakura, attempt a daring rescue mission while Naruto is in Orochimaru's clutches and they face off against Orochimaru's minions.
Well, perhaps in the fanfic, Orochimaru tortures Naruto as a form of revenge against the Leaf Village. He might use his various snake - related jutsu to cause pain and harm to Naruto. For example, he could make snakes constrict Naruto, slowly squeezing the life out of him while also injecting him with some sort of venom that causes excruciating pain. And all this while, Naruto is trying to find a way to break free and defeat Orochimaru, relying on his inner strength and the memories of his friends and his training.
Another plotline could be that Orochimaru is forced to train Naruto. Maybe the Hidden Leaf Village has some sort of leverage over Orochimaru. During the training, Naruto discovers some dark secrets about Orochimaru's past and his experiments. This knowledge could help Naruto in his future battles not just against Orochimaru if he turns on him, but also against other enemies who might have similar ideas. Naruto might also gain some new physical abilities from Orochimaru's training, like enhanced speed or strength.
One possible plotline could be Naruto being forced to serve Orochimaru due to some sort of blackmail or threat against his friends in Konoha. Maybe Orochimaru has some information that could endanger Naruto's loved ones if he doesn't comply. Another aspect could be Naruto initially pretending to serve while actually trying to find a way to take Orochimaru down from the inside. This would add an element of mystery and deception to the story.
He survives through his strong will. Naruto has an unwavering determination that refuses to be broken by Orochimaru's experiments. His inner strength and the chakra of the Nine - Tails within him might also play a role in withstanding the physical and mental torture of the experiments.
Well, Orochimaru is a very ambitious and somewhat deranged character. His motives for experimenting on Naruto could be multi - faceted. Firstly, he's always been obsessed with the Sharingan and other powerful kekkei genkai. Naruto, with his own powerful chakra source, might be a step in his research to create something that can rival or even surpass the power of the Sharingan. Secondly, Orochimaru is known for his experiments on humans to enhance their combat abilities. Naruto's natural strength and growth potential could be used to develop new combat - enhancing techniques that Orochimaru could then use for his own purposes, like building a more powerful army or just to satisfy his own scientific curiosity.