It depends on the specific context and the author's intentions. Sometimes, it might be considered canon, but without more details, it's hard to say for sure.
I'm not entirely sure about the very specific 'real story' of Kars for Kids. But generally, it's an organization that is known for collecting car donations. It uses the funds from these donations for various children - related causes, like providing educational support or care for children in need.
I'm not entirely sure as I haven't read it specifically. But generally, a light novel often has a unique story line, perhaps with complex characters and an interesting world - building. It might involve the adventures of the characters, their growth, and the challenges they face in the world of 'ultimate kars'.
One idea could be a crossover with the 'Jojo's Bizarre Adventure' universe where Kars interacts with other Stand users. Maybe he forms an unlikely alliance with a hero to defeat a common enemy.
I'm not familiar with the 'ultimate kars light novel' in detail. However, in most light novels, there are usually a protagonist and antagonist. So, Kars is likely the protagonist. As for the other main characters, there could be someone who opposes Kars, perhaps a rival with a different ideology or goal. There may also be characters that are important to Kars's development, such as a family member or a love interest.
The clash of two very different universes makes 'naruto kars fanfiction' interesting. Naruto's world is full of ninjas, chakra, and complex village politics. Kars, on the other hand, comes from a world with his own set of powers and rules. When combined, it creates a unique and unpredictable story.
To start a Kars crossover fanfiction, think about the conflicts that will arise. Kars is used to a certain way of life in his original story. When he crosses over, he'll face new challenges. Maybe he'll have to adapt to a different moral code or a new power hierarchy. This can be the starting point for your story, as you explore how he copes with these changes.
There's no way to really tell if it's common specifically for someone named Jojo. However, in general, reading fanfiction is a popular activity among fans of many different franchises. The Jojo series has a large and dedicated fan base, so it's likely that there are fans named Jojo who partake in reading fanfiction, but we can't say for sure how common it is without more data.
Perhaps this Jojo is interested in exploring different interpretations and stories within the Jojo universe that fans have come up with. Fanfiction often takes the existing characters, settings, etc. from the original Jojo series and creates new and unique storylines. So, this Jojo might be a big fan of the series and wants to see what other fans have imagined.