If Harry were to create a Horcrux in fanfiction, it would likely lead to a great corruption of his soul. Horcruxes are dark magic, and the act goes against all that Harry stands for in the original series. He might start to show signs of increased aggression, a detachment from his friends, and a growing attraction to the Dark Arts.
Well, it could be that Dumbledore, in some fanfic versions, figures it out first and then reveals it to Harry. Dumbledore is often portrayed as having a deep understanding of magic. He might have noticed some strange magical patterns or behaviors related to Harry that led him to suspect and then confirm that Harry was a Horcrux. And then he would tell Harry about it, which is how Harry comes to know.
Perhaps his father's old wand. It has a connection to his family and his heritage. Since it's a wand, it already has a certain amount of magical energy, so it could potentially be a suitable vessel for a Horcrux. And it would be a very interesting twist on the concept of a Horcrux as wands are not a typical choice.
One consequence could be that his connection to Voldemort becomes even stronger. This might lead to him being able to sense Voldemort's actions and thoughts more clearly, but also make him more vulnerable to Voldemort's attacks on his mind. Since the Horcrux is a part of Voldemort's soul, it could also start to influence Harry's personality, making him more aggressive or moody at times.
Yes, in some fanfiction, Harry Potter is considered a Horcrux. This concept adds an interesting twist to the original story, exploring different aspects of magic and the connection between Harry and Voldemort.
In this kind of fanfiction, it often shows Ginny's shock and the complex emotions she might have. She might be worried about Harry's fate, as being a Horcrux means he is tied to Voldemort in a very dangerous way. This discovery could lead to her trying to find a way to break the Horcrux connection without harming Harry.
In fanfic, it could be through a dark spell gone wrong. Maybe a spell that was meant to destroy the Horcrux instead backfired and caused it to merge with Harry.
Well, in some fanfictions, a Horcrux might be purified through powerful magic spells that are specifically created for the purpose. For example, a spell that can reverse the dark magic used to create the Horcrux in the first place.
Obviously, Harry Potter is one of the main characters since he is the one who is a Horcrux. His friends Ron and Hermione are likely to be main characters as well, as they are always by Harry's side in the original story and would play important roles in dealing with this new situation.
There's 'Harry's Hidden Horcrux'. This fanfic could show Harry creating a Horcrux during a time of great emotional turmoil. Maybe he's trying to preserve a part of himself that he feels is being lost in the fight against Voldemort. It would likely delve into the dark magic aspects and how it changes Harry.