Well, it could be about a fan - created story in the Naruto universe where a crystal is involved in hypnosis. Maybe it's a unique jutsu that uses a crystal for mind - control purposes within the story.
Since it's a Naruto - based fanfiction, Naruto, Sakura, and Kakashi are potential main characters. Naruto might be the one trying to stop the misuse of the hypnosis crystal. Sakura could be using her medical skills to help those affected by the crystal's hypnosis. And Kakashi might be using his wisdom and combat skills to deal with the threats associated with the crystal.
I'm not sure specifically what this 'naruto hypnosis crystal fanfic' is about as there could be many different interpretations. It might involve a story in the Naruto universe where a crystal is used in a way related to hypnosis, perhaps by a character to gain an advantage over others or for some other plot - related reason.
I don't know the exact main characters in this fanfic as it could be any of the characters from Naruto or even new ones created by the fanfic author. It might be Naruto himself using the hypnosis crystal for some noble purpose, or perhaps an antagonist who wields this powerful crystal.
It could be a wandering sage. These sages are often full of strange and powerful knowledge. They might see potential in Naruto and decide to teach him hypnosis as a way to expand his combat skills.
Hypnosis can make characters more trusting or more suspicious of each other. For example, if one character hypnotizes another to believe they are a friend, it can create a false sense of security. Or if a character discovers they've been hypnotized by someone they thought was a friend, it can lead to a breakdown in trust.
If Naruto hypnotizes Tsunade, it could initially disrupt her leadership. She might make uncharacteristic decisions that could throw the village into chaos. For example, she could start allocating resources in a strange way.
I'm not entirely sure if it's a hugely popular genre. It seems rather niche. While the Naruto fandom is large, this specific concept of hypnosis and'slave' in a fanfiction sense might not appeal to the mainstream Naruto fans. There are so many other more common themes in Naruto fanfictions like power - ups, new jutsu, and character relationships that are more popular.
I think 'naruto hypnosis slave fanfiction' might involve some sort of mind - control or trance - like states within the Naruto setting. Maybe it's about a villain using hypnosis to control a Naruto character and make them do things against their will, leading to all kinds of adventures and challenges for the other characters to overcome.
The unique aspect is the blend of the Naruto universe with the concept of hypnosis. It can create new and exciting plotlines. For example, characters' normal abilities can be altered or enhanced by hypnosis, like a ninja being hypnotized to believe they have a new jutsu.