Well, the plot could involve Naruto getting tired of the shinobi life. He might start hanging out with the wrong crowd in the village, like some small - time thugs. He could use his ninja skills in illegal ways, for example, stealing valuable scrolls not for the good of the village but for his new 'gang'. His friends like Sasuke and Sakura would be shocked and try to bring him back to the right path.
He would become more cynical. Instead of his usual optimistic self, he'd view the world in a darker light. His trust in people would be severely damaged.
One possibility could be that Naruto is drawn to boxing because of its physicality and the determination it requires. He might see it as a new way to test his strength and endurance outside of ninja battles. Maybe he starts training with a local boxing coach who sees his potential and helps him develop his skills.
Power struggles are common. Just like in the original Naruto where there are power hierarchies among the villages, in gangster fanfiction, there are power plays between different gangs. For example, they might fight over control of certain areas or valuable ninja resources.
Perhaps Naruto's transformation into a Predator - like being changes his appearance. He might have some Predator - like physical features such as glowing eyes or enhanced strength. This could lead to his friends initially being scared or confused, but as they see him use these new powers for good, they come to accept him. In the story, he could also learn to control these powers, so they don't overtake his original ninja nature.
One possible scenario in a fanfiction where Naruto becomes Pein could be that Naruto is exposed to some dark jutsu that alters his mind. This jutsu might be related to the Rinnegan's power. As a result, he starts to adopt Pein's ideology of bringing pain to the world in order to create peace. His friends would be shocked and try to bring him back to his normal self.
Well, Naruto as a genie would be a really cool idea for a fanfiction. His character already has a strong sense of justice and a big heart. As a genie, he would be able to spread his positive influence even more widely. Imagine Naruto granting the wish of a poor village for food and resources. He could also use his genie powers to create illusions on a grand scale, fooling the enemies of the village. And his bottle or lamp (where he is trapped as a genie) could be hidden in some super - secret location in the Hidden Leaf.
One possible scenario could be that Naruto is transported to the Flash's universe and somehow gains the powers of Savitar. He might use Savitar's speed in his own unique way, like combining it with his shadow clones to create a sort of blitzkrieg attack. Maybe he would also struggle with the darker aspects of Savitar's power, as Naruto is typically a more positive - minded character.
Well, it could be about a female character who is like a gangster queen in the Naruto world. Maybe she's a powerful kunoichi who rules an underground organization. She could be involved in illegal trading of ninja tools or secrets. And she might cross paths with Naruto and his friends, either as an enemy or an unexpected ally.
This question needs to be judged according to the specific context and description. However, generally speaking, if a student becomes a boss of the underworld, then this could be a novel or movie about the underworld life and gang struggles, or it could be a movie or novel with the boss as the main character. However, it should be noted that this plot may involve some violence, crime, and bloody scenes. If you feel uncomfortable with these scenes, it is recommended not to watch.