Yes, there are some out there. You can start by looking on fanfiction websites like FanFiction.net or Archive of Our Own. Just search for 'kyuubi naruto x moka' and you'll likely find a variety of stories with different themes and plotlines.
One common theme is the exploration of their combined powers. Since Naruto has the power of the Kyuubi and Moka has her own unique vampire abilities, stories might focus on how they use their powers in battles or to protect each other.
One interesting storyline could be Naruto and Moka teaming up to fight a common enemy. Since Naruto has the power of the Kyuubi, he could bring his combat skills and chakra control, while Moka, with her vampire abilities, could use her super strength and unique vampire powers like her Rosario. They might face a powerful demon or an evil organization that threatens both their worlds.
In a fanfic, the merging could also be due to a common threat. Suppose there is a dark force that wants to conquer both the ninja world and the vampire world. To fight this threat, Naruto and Moka's worlds start to merge gradually. This would result in unique alliances. For example, ninja and vampires might have to work together, with Naruto and Moka leading the way. They would need to find a way to combine their different fighting styles and powers, like Naruto's shadow clones and Moka's blood-based attacks.
One idea could be a crossover adventure where Naruto and Moka find themselves in a strange new world together. They have to combine their unique abilities, Naruto's ninja skills and Moka's vampire powers, to survive and find a way back home.
Inner Moka is also likely to be in these fanfictions. Her more aggressive and powerful side compared to outer Moka can create different scenarios. For example, she might be initially hostile to Naruto but then gradually warm up to him as she sees his good qualities.
Communication might be a big issue. Naruto comes from a world where people communicate in a certain way, and Moka is from a different, more supernatural - oriented culture. They may misunderstand each other's intentions or not be able to fully convey their thoughts. Also, if they are in a world that is not familiar to both of them, they would have to adapt quickly to the new environment while also dealing with their own personal differences.
Naruto in Moka's body would find it challenging to maintain his usual exuberance. His natural inclination to jump into action would be curbed as he has to adjust to Moka's more ladylike ways. He might become more perceptive of others' emotions, as Moka's character may be more in tune with such things. Moka in Naruto's body would embrace his can - do spirit. She would become more competitive and would be eager to prove herself in the ninja world. Her personality would transform from the somewhat mysterious and alluring one to a more upfront and action - oriented one, much like Naruto's.
Yes, in some fanfictions, Naruto is often depicted as the Kyuubi or having a very close connection to it. This can lead to really interesting and unique storylines that deviate from the original plot.
Yes, there are likely some interesting 'Naruto' and 'Moka Lemon' fanfictions out there. You can start by looking on popular fanfiction websites like FanFiction.net or Archive of Our Own. Just search for the relevant tags, and you might find some unique stories that combine elements from both.