Well, it could be that the fanfic has a particular aesthetic where green is a color that represents something special. It might be related to a specific group or place in the story that Harry is associated with. And the way the author has crafted the descriptions, from his hair color to his skin tone, green just seems to enhance his overall appearance.
Maybe it's because green symbolizes freshness and vitality in the fanfic, which complements Harry's character.
In the fanfic, the author might have described Harry's features in a way that makes green a very flattering color on him. For example, if Harry has bright eyes, green could make them stand out even more. Also, green could be associated with certain positive traits in the context of the story, like a connection to nature or magic, which in turn makes Harry look good when wearing it.
The color combination of his other features with green.
In fanfictions, Astoria may look up to Harry because of his heroism. He defeated Voldemort, which saved the wizarding world. This is a huge accomplishment that would naturally make someone like Astoria, who lives in that world, admire him. His actions were selfless and he risked his life many times.
Green peppers were usually green, but there were also red, yellow, orange, and purple varieties. Green peppers could be square, square lantern, or spiral in shape. Green peppers had thicker fruits and crispy meat. The picture of the green pepper could be found in the relevant search results.
It could be a great fanfic. If it focuses on Harry Potter's admiration for the Weasley family, it might explore deep friendships and the sense of family that the Weasleys represent. For example, Harry's relationship with Ron Weasley is one of the most important in the series, and this fanfic could delve into that further.
Perhaps Harry has his own vision of Gryffindor and the fanfics he's seen don't align with it. He might have a deep - seated understanding of what Gryffindor means to him, like courage, loyalty, and friendship in a very personal way. The fanfics, on the other hand, might focus on more superficial or inappropriate aspects of Gryffindor for his taste, such as focusing too much on power plays or false bravado rather than the true essence of what makes Gryffindor great.
Maybe he has his own personal reasons. He could be afraid of failure, or perhaps he doesn't like the competitive environment. Another possibility is that he has some moral objections to the nature of the competition in the fanfic.
In some fanfics, Harry might hate Dumbledore because he feels Dumbledore has been using him all along as a tool to defeat Voldemort. Dumbledore has been making decisions for Harry without fully considering Harry's feelings and desires. For example, he didn't tell Harry about the prophecy until it was almost too late, and Harry might see this as a form of manipulation.
Maybe the writer wants to create a unique plot twist. In some fanfics, authors like to deviate from the original relationship to explore different character dynamics.
There could be ethical reasons. Fanfic sometimes involves using characters and settings created by others without proper authorization in a more complex way than just being inspired. Harry might not want to get involved in teaching something that has such potential legal and ethical gray areas.
It could be that in the fanfic's plot, McGonagall has some past connection to Harry's enemies. So, her hatred towards Harry is a result of her loyalty to those she has a history with. This would create a lot of drama and conflict within the fanfic's story.