One possibility could be through a magical accident. Maybe a spell gone wrong during a Hogwarts experiment transports Harry to the Bleach universe. There he witnesses Grimmjow's power and charisma and becomes a fan. Another reason could be that Harry, tired of the constant danger in his own world, is drawn to Grimmjow's fearless and brash attitude. It could also be that a cross - universe book or some form of media makes its way into Harry's hands, introducing him to Grimmjow and making him a fan.
In a fanfiction scenario, Harry Potter could become a Grimmjow fan if he was exploring different forms of magic or power. Grimmjow is a powerful Arrancar in the Bleach universe. Harry, always curious about new magical abilities, might stumble upon information about Grimmjow. His unique Hollow powers, his unapologetic nature, and his drive to be the strongest could all appeal to Harry. Maybe Harry is looking for inspiration outside of the wizarding world, and Grimmjow provides that in terms of a different kind of power and a different code of conduct.
Harry could start collecting things related to Superman within the magical world. Since there's no actual Superman merchandise there, he might use magic to create things like Superman's cape or symbol. He could also try to incorporate Superman - like values, like truth and justice, into his own code of conduct at Hogwarts, which could lead to some interesting interactions with his friends and teachers who might not understand this new influence at first.
Well, if Harry Potter becomes a Shazam fan, he might start comparing the magic in his world to Shazam's powers. Maybe he'd be fascinated by how Shazam gets his powers from the ancient gods. He could even try to find similarities between spells in his wizarding world and the powers Shazam uses. For example, Shazam's super strength could be like the strength - enhancing spells in Harry's world.
Well, in fanfiction, the writer could use a magic portal to transport Harry Potter to the Star Wars universe. Maybe he's on the run from Voldemort and stumbles upon this strange new world. Once there, he gets intrigued by the Mandalorian culture, with their cool armor and code of honor.
Well, it could happen if there was some sort of magical cross - over event. Maybe a powerful wizard accidentally casts a spell that transports Harry into the world of Pokémon, specifically the world of Eevee. And there, he gets fascinated by the cute and diverse forms of Eevee.
Well, in some fanfiction, it could be due to dark magic gone wrong. Maybe a spell was cast that had unexpected consequences and turned Harry into a basilisk. Another possibility is that some ancient magic related to the basilisk was misused or backfired on him.
Perhaps he is forced into a new situation where he has to adapt and become a warrior. For example, if Voldemort somehow manages to take over the wizarding world completely and Harry has to flee to a non - wizarding land. There, he discovers that the only way to fight back and survive is to become a warrior. So, he starts training in their ways, learning their combat styles and gradually becomes one of them.
It could be that after the war, Harry feels a need for a new purpose. He might start learning about Muggle healing methods out of curiosity. His quick - learning skills, which he developed during his years at Hogwarts, would help him quickly understand medical concepts. He could also use magic to heal some ailments that normal medicine can't, thus becoming a very unique doctor.
In this fanfiction scenario, Harry Potter could become a hunter due to a spell gone wrong. Maybe he was experimenting with some ancient magic and it accidentally teleported him to a realm where hunting is a way of life. He would bring his sense of justice with him. In the wizarding world, he fought against dark wizards; now, he could use that same determination to protect the innocent in the hunter world. He could also introduce some of his magical knowledge to the hunters, creating a unique blend of magic and hunting skills.
Well, he might completely change the power structure in the wizarding world. He could rewrite the rules at Hogwarts, for example, making it more focused on combat training against the dark arts. He might also form a new alliance with the magical creatures, using their unique abilities to strengthen his rule.
Harry could also be a great Quidditch coach. He was an excellent Quidditch player himself. He would be able to train students in the skills of flying, teamwork, and strategy. He could pass on his love for the sport and perhaps even lead the school team to many victories. He would know how to spot potential in young players and help them develop their talents.