Typically, in 'naruto has foxfire' fanfiction, Naruto's power gets an extra dimension. The foxfire is often related to his connection with the Nine - Tails. It might be a new form of his chakra, or a special ability he discovers.
The mystery around foxfire itself makes these stories spooky. Foxfire is a natural phenomenon that glows in the dark, but when it's associated with ghosts, it takes on a whole new level of eeriness. People don't really understand what causes it, so it's easy to attach supernatural beliefs to it.
They are also typically shown to have a different sense of time and values compared to humans. This difference creates interesting conflicts and also opportunities for deep emotional connections in the romance. For instance, a Kitsune might value loyalty in a way that is both similar and different from a human, which can lead to both misunderstandings and profound moments of understanding in the relationship.
In a particular foxfire ghost story, a group of hikers saw a foxfire in the middle of a forest trail. As they got closer, they heard strange whispers. The foxfire then disappeared and reappeared a short distance away. They later learned that the area was once a battleground, and the ghosts of the soldiers were said to be associated with the foxfire, perhaps trying to tell their story.
One great 'naruto has foxfire' fanfiction is 'Naruto's Foxfire Adventure' on FanFiction.net. It has an interesting plot where Naruto discovers a new form of his chakra that resembles foxfire and he uses it to overcome powerful enemies.
The Kitsune aspect can make Naruto more mysterious and alluring to Hinata. His unique powers and form can be something that draws her in and makes her see him in a new light.
Yes, there are likely fanfictions out there with such a concept. Fanfiction communities are very creative and often come up with unique and sometimes strange combinations. Naruto is a popular series, and the idea of incorporating kitsune (fox - like beings in Japanese mythology) and yaoi (male - male relationships in fanfiction) is not unheard of in the realm of fan - created content.
Kitsune light novels have a certain level of popularity. Their appeal lies in the unique concept of Kitsune. People who like stories with elements of magic, mystery and different cultures find them interesting. Also, the Kitsune's characteristics like their intelligence and shape - shifting abilities make for exciting plotlines, which contribute to their popularity.
Kitsune are foxes in Japanese mythology. However, 'erotic stories' related to them involve inappropriate and often adult - themed content, so I can't provide details on such stories.
It might give Naruto new types of jutsus. For example, if the Kitsune have the ability to create illusions, the mask could grant Naruto the power to use more advanced genjutsu. He could use these illusions not only in battle but also to deceive his enemies in strategic ways outside of combat.