There's no known connection between the Joker, who is a character from the Batman universe, and the creation or promotion of Harry Potter fanfiction. Fanfiction typically grows organically from the passion of Harry Potter fans who want to explore different stories within that magical world. The Joker has no role in that fictional realm of Hogwarts and its related stories.
I'm not sure if there is a specific instance where a 'Joker' would be directly involved in raising Harry Potter fanfiction. Usually, fanfiction is created and promoted by fans themselves within the fan community, not by a character like the Joker.
The idea of the Joker being related to raising Harry Potter fanfiction is rather strange. The Joker is a villain in a completely different fictional context. Harry Potter fanfiction is a product of the creativity of Harry Potter fans. They write it, share it, and build a community around it. There's no way the Joker, with his chaotic and dark nature from the Batman series, would have any influence on the growth or raising of Harry Potter fanfiction.
Well, if we're talking about the Joker from the Batman universe, there's no canonical information indicating he has any knowledge of Harry Potter fanfiction. He's more preoccupied with chaos in Gotham. But in some wild crossovers in fan - created works, he might be depicted as knowing it, just for the fun of mashing up different universes.
The Rani might raise Harry Potter by exposing him to rare and powerful magic, while also teaching him the importance of responsibility and caution.
He probably uses his magic in a discreet way. For example, he could use a charm to make Teddy's toys more interesting. And he would rely on his own experiences of growing up without parents to give Teddy a loving and stable environment.
The Joker as a professor in Harry Potter fanfiction? That's a wild idea. He could be the professor of Dark Arts in a very different way. Instead of the traditional Dark Arts that the wizarding world knows, he would introduce his own form of 'dark art' which is more about psychological torture and mind games. His classes would be full of his maniacal laughter and unexpected challenges. Students would have to constantly be on their toes, not knowing what he'll do next. He might even use his students in his elaborate schemes against the other professors or the Ministry of Magic.
It could be that the assassin was initially a victim of some dark wizard's experiment. Harry, being the hero he is, feels responsible for the child and decides to raise him. In the process of raising, he unknowingly nurtures the assassin-like qualities in the child because of the unique circumstances and challenges they face together.
One possible plotline could be that Harry, after some dark magic influence or a strange accident, starts to show Joker - like behavior at Hogwarts. He might play cruel pranks on his classmates and teachers, using his magic in unexpected and unethical ways.
One common theme is the clash of two different worlds. The orderly and magical world of Harry Potter with its own set of rules and the chaotic, lawless world that the Joker represents. Another theme could be the corruption of innocence. The Joker might try to influence the young wizards and witches at Hogwarts, corrupting their pure intentions.
It would be really strange. Harry Potter is from a magical world of wizards and witches, while the Joker is a chaotic and often dark character from the Batman universe. Maybe in this fanfiction, Harry could have the Joker's unpredictable nature and use his magic in really devious ways.
Yes, there might be some out there. Fanfiction is a vast world where people combine different fictional universes in creative ways. You can try searching on popular fanfiction websites like Archive of Our Own or FanFiction.net. However, the quality and content can vary greatly.
Sorry, but without more information, it's impossible to determine the author of 'granger's raise harry potter fanfiction'. There are countless fanfiction works in the Harry Potter fandom, and this one doesn't seem to be a widely known one in terms of its authorship.