Often, it develops through shared hardships. For example, they might be captured by a powerful enemy and have to escape together. During this time, they learn to trust each other more deeply.
In fanfiction, Naruto and Sasuke might become friends when they have to protect someone important to both of them. Let's say it's a young orphan who reminds them of their own difficult pasts. Naruto's positive attitude and Sasuke's protective nature would kick in. They would work together to keep the child safe. Through this shared experience and the emotions it stirs, they start to see each other in a new light and become friends.
A fanfic could explore a scenario where Sasuke decides to teach Naruto some basic Sharingan techniques. Despite Naruto not having the Sharingan, Sasuke believes that Naruto's ability to learn quickly and his unique chakra could allow him to adapt some of the Sharingan's skills. This would strengthen their friendship as they train together and Naruto starts to understand Sasuke's power on a deeper level.
A possible plot could be that they discover a new and dangerous jutsu that has been lost for centuries. They decide to train together to master it so that it can be used for the good of the village. Along the way, they learn more about each other's pasts and their friendship deepens.
Some fanfictions focus on the emotional side of their friendship. Like, Sasuke has a difficult time dealing with his past traumas and Naruto is there for him every step of the way. They have heart - to - heart conversations and through this, their friendship deepens. It's not just about fighting side by side but also being there for each other during the tough times.
One interesting plotline could be Naruto and Sasuke going on a journey together outside of the Hidden Leaf Village to explore a new land filled with strange creatures and unique ninja techniques. They could face challenges that force them to rely on their friendship more than ever.
The fanfic could be centered around Sasuke's best friends, Naruto and Sakura, and how they interact with Sasuke's Sharingan. For instance, Naruto might be curious about the Sharingan's abilities and constantly ask Sasuke to show him new tricks. Sakura, being a medical ninja, could study the Sharingan's effects on Sasuke's body to ensure he doesn't overuse it and harm himself.
In a fanfic like this, Sasuke's Sharingan could be the key to unlocking a hidden power within his best friends. Maybe his Sharingan has a special connection to Naruto's Nine - Tails chakra. As they fight side by side, Sasuke uses his Sharingan to guide Naruto in controlling the Nine - Tails better. Sakura, on the other hand, could learn new medical jutsu inspired by the insights from Sasuke's Sharingan, deepening their bond as they all grow stronger together.
A possible plot could be that Naruto and Sasuke are sent on a diplomatic mission to another village. Along the way, they face many challenges like harsh weather and bandit attacks. Naruto's ability to stay positive and Sasuke's combat skills help them survive. During their journey, they have deep conversations about their dreams and fears. This new understanding of each other makes them realize they have more in common than they thought, leading to friendship.
I like 'Naruto and Sasuke: A Different Path'. In this fanfic, their friendship is explored in a unique way. Instead of the usual storylines, it focuses on how they might have become friends in a more peaceful Konoha. They learn from each other's skills and share their dreams, which is really heartwarming.