One idea could be that Naruto wears the emotionless mask to hide his true feelings of pain and isolation after a major event in the village. He might be using it as a way to distance himself from others while he figures out his new place in the world. Another plot could involve the mask being a magical or cursed item that slowly starts to change Naruto's personality, making him more cold - hearted than he really is.
Well, perhaps in the fanfiction, Naruto dons the emotionless mask as part of a mission. He has to infiltrate an enemy organization where showing any emotion could blow his cover. This leads to some interesting situations where his friends start to worry about him because they don't understand why he's acting so differently. Or it could be that the mask was given to him by a mysterious figure who has an ulterior motive for making Naruto suppress his emotions.
Perhaps Naruto is cursed by a powerful jutsu that turns him into an emotionless killer. He begins to hunt down the shinobi who he believes are threats to the Hidden Leaf, not caring about the consequences. However, his friends like Sasuke and Sakura notice the change and try to break the curse. They embark on a journey to find a way to reverse the effect while also protecting Naruto from himself.
Well, perhaps a plot where Orochimaru manages to get his hands on Naruto and uses some dark experiments to turn him into an emotionless tool. Naruto then starts to carry out Orochimaru's bidding, like stealing valuable scrolls from other villages. Or maybe in a parallel universe, the Akatsuki capture Naruto and brainwash him into an emotionless tool to use against the Hidden Leaf, and his friends have to find a way to break the spell.
One idea could be that Naruto, in this fanfic world, is emotionless due to some dark magic. In the Bleach universe, he could be a rogue soul reaper who doesn't follow the normal rules because of his lack of emotions. For example, he might befriend Ichigo but in a very cold and calculating way, using Ichigo's power for his own ends without really feeling any guilt or friendship in the true sense.
In an 'emotionless Naruto fanfiction', it could be that Naruto loses his emotions after a great loss, like the death of Iruka Sensei. He shuts down emotionally and becomes a lone wolf, focusing only on missions. However, his friends, especially Sasuke, realize that he needs to regain his emotions to truly be himself and start a journey to help him.
Another plot could be that Naruto was experimented on by Root to be emotionless. He is then pitted against his old friends in a battle. His friends try to reach out to the old Naruto inside him during the fight. This leads to a series of internal struggles within Naruto as he starts to feel the faintest glimmers of his former emotions resurfacing.
One idea could be a story where Obito's mask holds a hidden power. For example, it could be a key to an ancient jutsu that was sealed away long ago. Another plot could involve a character trying to steal the mask for its significance in the ninja world.
One interesting plot could be a story where the Kitsune mask holds a hidden power that Naruto discovers accidentally. He then has to learn to control this power without being consumed by it, all while facing off against new enemies who are also after the mask's power.
Maybe the skull mask was once worn by a powerful and long - forgotten ninja clan. In the fanfiction, the main character stumbles upon the mask and is then hunted by other clans who fear the power it holds. The story could revolve around the main character's struggle to keep the mask safe while also trying to figure out how to use its power to protect themselves and their village.
A great plot idea could be that there is a masked figure who seems to be causing chaos in the village. Naruto suspects it's someone he knows, but as he digs deeper, he realizes it's an imposter using the identity of a well - liked shinobi. Or perhaps the mask is a symbol of a long - forgotten clan, and Naruto is the key to unlocking its secrets. This could lead to adventures where he has to travel to old clan ruins and face challenges related to the clan's past. Also, the masked character could be a time - traveler from Naruto's future, trying to change something in the past.
A possible plot in this fanfiction could be that Naruto is magically transformed into a girl and has to wear female clothes. As he adjusts to this new form, he realizes the differences in how people treat him. He might use this opportunity to learn more about the female ninja in his village and their training methods. He could also get involved in a relationship while in his female form, which would be really interesting as he tries to navigate his true identity and his new - found feelings.