Obviously, Harry Potter himself is still very popular. Fanfiction often focuses on his growth and his final steps towards defeating Voldemort.
Draco Malfoy can be quite popular too. Some fanfictions explore his possible redemption arc in the seventh year. He could be in a difficult position, still having ties to the Death Eaters through his family but also starting to see the error of their ways. This internal struggle makes him an interesting character to write about in the context of the final year at Hogwarts.
One great fanfiction idea could be Harry dealing with the Triwizard Tournament challenges in unique ways. Maybe he discovers a hidden power within himself that helps him out during the tasks, like a new form of magic he didn't know he had.
Harry Potter himself is always popular. In 5th - year fanfiction, readers often like to see his growth and how he copes with the various challenges. Hermione is also a favorite. Her intelligence and loyalty make her an interesting character to explore further in fan - created stories.
Hermione is also a favorite. In fanfiction, she can be shown delving even deeper into her studies, perhaps uncovering secrets about the wizarding world's history that are relevant to the 6th year events. Also, her relationship with Ron and how she deals with her own feelings and insecurities is a popular theme. Ginny is another popular character. Fanfictions might focus on her as a powerful witch in her own right during Harry's 6th year, showing her skills on the Quidditch pitch and her influence among the students.
A possible plotline could be that Hogwarts itself becomes a sort of magical battleground earlier than expected. The Death Eaters try to take over the school completely, and the students and remaining teachers have to fight back in a sort of guerilla warfare within the castle walls. This would change the whole dynamic of the seventh year, with classes being interrupted and students having to use their magic in real - life combat situations.
One popular original character is a new student who has a unique magical ability. For example, a character who can communicate with magical creatures in a way no one else can. This character often befriends Harry and helps him in unexpected ways during their 7th year.
Harry Potter himself is also very popular. He could be seen as an older, wiser apprentice passing on his knowledge of fighting dark magic to the new generation of students. His adventures against Voldemort give him a lot of experience to share.
Draco Malfoy is often a popular character in these fanfictions. After Hogwarts, he might be trying to redeem himself, or there could be a love story between him and a character like Hermione. His complex past and family history make for interesting storylines. Another popular character could be Neville Longbottom. He has grown so much during his time at Hogwarts, and in fanfiction, he could be a great teacher at Hogwarts, passing on his knowledge of Herbology and his courage to the new students.
Sirius Black can be a very popular character in 'harry potter 5th year fanfic'. Since he has a close relationship with Harry, fanfic writers might focus on his interactions with Harry during this year. Maybe he gives Harry some secret advice about dealing with the Ministry or the Death Eaters, which adds an extra layer of intrigue to the story.
A plot could be that Harry has premonitions about the Triwizard Tournament tasks before they happen. These premonitions are not clear at first, but as he gets closer to each task, he starts to understand them better. It adds an element of mystery and foreshadowing to the story.
Another important character could be a new student or a transfer student. This character could bring in a fresh perspective and perhaps be a link to the new threat or mystery in the story. The Headmaster or Headmistress, whether it's Dumbledore (if he's still alive in this fanfiction) or someone else, would also be very important as they are responsible for the safety and well - being of the students during Harry's last year at Hogwarts.