The works of Masashi Kishimoto include various narrative arcs, but the central theme always revolves around the relationship between two characters, Sasuke and Naruto. This is why fans often have numerous questions regarding the intricacies of this complex relationship. One of the most intriguing questions is why Sasuke considers Naruto as “his only friend”.
The origin of this question stems from the inquiry, “If Naruto is Sasuke’s only friend, then what is Sakura to him?”

In truth, Sasuke views Sakura merely as a teammate, while she later becomes a pivotal figure in his quest to achieve his goals. Subsequently, during the Fourth Great Ninja War, she aids him in his endeavors. Sasuke’s feelings for Sakura only begin to develop after the final battle with Naruto in the Valley of the End. At that moment, he realizes that his own actions have driven away those who genuinely wanted to help him.
However, unlike Sakura, Naruto fully understands the burdens that Sasuke carries. In fact, even before they formally team up, both characters have already forged a connection through their shared experiences. Thus, even though they walk different paths, Sasuke knows that Naruto is the only one who truly understands him, and vice versa.

The bond between Sasuke and Naruto becomes even clearer when Itachi acknowledges that Naruto is the only one capable of influencing his younger brother’s path. In the “ninja way” of Naruto, the path he chooses is a reflection of the bonds he forms, even when they lead him to confront his own reality.
In fact, Masashi Kishimoto discussed this topic during an interview in 2012 with Weekly Shonen Jump Alpha. He elaborated on how he aimed to develop the relationship between Sasuke and Naruto.
“Sasuke is always in a dark place. Naruto and Sasuke progress like a pair. Therefore, when writing about Naruto, I always have to consider Sasuke. They are like two sides of a coin, akin to light and shadow.”