Yes, there are Kingdom Hearts fanfictions involving Naruto. Fanfiction writers often like to cross over different popular franchises, and Naruto and Kingdom Hearts are both well - known in their own right. So it's not uncommon to find fan - created stories that blend the two universes together, with Naruto characters in the world of Kingdom Hearts or vice versa.
It could be about a lot of things. Maybe it's a story where Naruto's darker side exists in the Kingdom Hearts universe. It might involve Naruto characters having to deal with the Heartless or Nobodies while Naruto himself is struggling with his inner darkness. For example, Naruto could be on a journey to find a way to control his dark side in a world filled with the unique threats and magic from Kingdom Hearts.
Power and growth are also common themes. Naruto often brings his ninja skills and determination into the Kingdom Hearts world. He has to adapt and grow stronger to face the new threats there, all while managing his relationships in the harem. Friendship is another aspect, as he forms new bonds with characters from Kingdom Hearts, which sometimes also play into the harem dynamic.
One common theme is the struggle against darkness. In both Naruto and Kingdom Hearts, darkness is a significant element. So in these fanfictions, characters often have to battle their inner demons or external dark forces. For example, Naruto might have to face the darkness within himself in the context of the Kingdom Hearts world.
One concept could be Naruto and his friends being Keyblade wielders. They could travel between different worlds in the Kingdom Hearts style, using their ninja abilities along with the power of the Keyblade. For instance, Naruto's Rasengan could be combined with a Keyblade attack. Another idea is that the Akatsuki are like the Organization XIII in Kingdom Hearts, with each member having their own unique powers and goals related to both the Naruto world and the Kingdom Hearts concepts of hearts and darkness.
Well, the 'kingdom hearts end to beasts story' could have multiple meanings. Firstly, it might be about the end of the Beast's personal story, like how he overcomes his inner demons and finds true love or peace. It could also be about how his story ends in relation to the overall Kingdom Hearts narrative. Maybe it involves his interaction with other key characters at the end, like Sora or Riku. It could be that his story ends with a great sacrifice for the greater good, or perhaps it's a happy ending where he is reunited with Belle and his castle is restored to its former glory. All these aspects could be part of what this 'end to beasts story' entails.
The 'kingdom hearts 3d full story' is important as it likely contains the complete narrative of the Kingdom Hearts 3D game. It could include all the character arcs, the plot developments related to the different worlds visited, and the overarching battle between light and dark. It helps players fully understand the game's lore and how it fits into the larger Kingdom Hearts universe.
I'm not aware of any official gay stories about Sora in Kingdom Hearts that involve something called 'Tentacle Kingdom Hearts'. Kingdom Hearts is mainly a story about friendship, light, and dark, and while there are diverse interpretations among fans, this seems rather unorthodox and not part of the main narrative.
You can try fanfiction websites like FanFiction.net or Archive of Our Own. They have a wide range of fan - made stories, and you might be able to find the 'dark naruto kingdom hearts fanfiction' there.