Power dynamics is a common theme. Yujiro is often depicted as extremely powerful, and the relationship with the OC can be shaped by this. For example, the OC may be in awe of his strength or try to prove themselves equal to him.
When writing a Harry Potter and Yujiro Hanma fanfiction, it's important to establish the rules of the combined world early on. Will Yujiro be able to use magic? If not, how will he defend himself against magical attacks? You can also play with the idea of cultural differences. Yujiro comes from a very different kind of world compared to the wizarding world. This can lead to some interesting misunderstandings and comical situations. For instance, Yujiro might think the Sorting Hat is some kind of strange creature trying to attack him and try to fight it off. As you write, keep the pacing right, not too slow or too fast, and make sure the story has a satisfying ending, whether it's a happy ending or a more bittersweet one.
One interesting Yujiro Hanma fanfiction could be about his early days of training. It might explore how he developed his extreme strength and fighting skills. Maybe it shows his encounters with various opponents during his youth and how he overcame them to become the fearsome fighter he is known as.
It depends on how it's written. If it's written in a way that is just for shock value or to promote violence in an inappropriate way, then it's not appropriate. But if it's part of a plot that is exploring complex relationships or character development in a non - glorifying way of violence, it could be considered within the realm of acceptable fanfiction.
In a community - based '3 slaps true story', the significance of the three slaps could be related to the norms and values of that community. For instance, it could be a way to enforce a moral code. If someone broke an important rule, the three slaps could be a form of public shaming or a way to make them realize their mistake. Without knowing the details of the story, it's all just speculation though.
Probably not as popular as some of the more mainstream Naruto fanfics that follow the typical romance or adventure themes. However, there might be a niche group of fans who enjoy exploring these darker and more controversial plotlines. It depends on how much the Naruto fan community as a whole is willing to accept deviations from the original story's tone.
Definitely not. 'Three Slaps' is most likely a work of fiction. Usually, such stories are made up to entertain and engage the readers rather than being rooted in reality.
One possible plot could be a crossover where Yujiro Hanma somehow finds his way into the wizarding world of Harry Potter. Maybe he's on a quest for ultimate power and hears rumors of the powerful magic there. He could start challenging the most powerful wizards, like Dumbledore, thinking their magic is just another form of strength to be conquered.