I'm not aware of a specific fanfiction with this exact plot. It could be a very dark and disturbing concept. It might be exploring some extreme 'what - if' scenario where Naruto, from the Naruto universe, is somehow thrust into the Five Nights at Freddy's (FNAF) world and meets a gruesome end. But this seems like a very niche and potentially inappropriate crossover idea.
Honestly, this kind of fanfiction might be hard to find as it combines two very different universes in a rather extreme way. The Naruto series is mainly about ninjas, friendship, and growth, while FNAF is a horror game. Mixing them in such a violent way may not be in line with the overall themes of either franchise. Maybe it was created by a very creative but also a bit dark - minded fan who wanted to explore the boundaries of fan - created content.
One interesting concept could be the psychological horror of being stuffed into a suit. It gives a sense of claustrophobia and the horror of being trapped in an inanimate object. Another could be the mystery behind who is doing the stuffing and why. It adds an element of suspense to the fanfiction.
Often, there's the victim who gets stuffed in the suit. This character could be an employee who made the wrong move in the haunted pizzeria. And then there are the animatronics like Freddy, Bonnie, and Chica which are usually central to the story as they are either the cause of the stuffing or part of the horror that the stuffed character experiences.
Naruto could develop a more refined and sophisticated side. The suit symbolizes a new level of maturity. He might become more aware of the political and diplomatic aspects of being a ninja leader. For example, he starts to use more words and less brute force in negotiations.
Sakura could be one of his allies. She would be initially shocked by Naruto's new look in the Vader suit but would quickly realize it's still him. She could use her medical skills to help Naruto if the suit has any negative physical effects on him. Another could be Kakashi. He would be very intrigued by the suit and would use his wisdom to guide Naruto in controlling whatever new powers it gives him.
It could be from a foreign land. Maybe some traveling merchants brought it to the Hidden Leaf Village. They lost it on their journey and Naruto just happened to stumble upon it.
The talking stuffed animal could also be a plot device. Maybe it holds a key to a mystery. For example, it could have a map hidden inside it that leads to a powerful weapon or a secret location that is crucial for the safety of the Hidden Leaf Village.
In fanfiction, the naruto kyuubi suit can change his appearance quite a bit. His hair could become more wild and take on a reddish tint, like it's being influenced by the Kyuubi's chakra. His eyes might glow a different color, perhaps a deep red. Also, the suit itself could be form - fitting and have a pattern that resembles the Kyuubi's fur. This makes Naruto look more intimidating and shows his connection to the powerful nine - tailed fox.
The plot might be that Naruto has been invited to a grand celebration in a far - off land. He dons a suit for the occasion. There, he meets old friends and foes alike. He could get into some friendly competitions in his suit, like a formalized ninja sparring. Also, there could be a sub - plot where he has to protect a valuable artifact during the event, all while looking sharp in his suit.
There might be a fanfiction where the FNAF animatronics are brought into the Naruto world. The animatronics' strange and somewhat creepy nature would contrast greatly with the ninja world. The shinobi would be both intrigued and cautious of these strange mechanical creatures, and perhaps they would try to find a way to either use them or get rid of them.
The unique feature is the crossover aspect. Combining Naruto's ninja - filled world with the horror - filled FNAF world creates a very different and exciting setting. For example, Naruto's jutsu in the spooky FNAF locations make for some cool scenes.