After the final battle, Harry and Ginny's relationship in fanfiction can take many different paths. Some fanfictions depict them as immediately getting engaged and starting to plan their future together. Others show them taking it slower, with Harry dealing with his PTSD from the war and Ginny being there for him every step of the way. They might also get involved in the rebuilding of the wizarding world, working side by side, which further cements their relationship.
They could go on a quest to discover hidden magical artifacts. For example, they might search for ancient spells that were lost during the war. This would not only be exciting but also help in the restoration of the wizarding world's magical knowledge.
In fanfiction, they might start to rebuild their lives together. They could focus on their relationship more deeply, perhaps getting married and starting a family soon. Harry could finally have the peaceful life he always desired with Ginny by his side.
They might get married and start a family right away. In fanfiction, it's common to see them settling down and having kids, living a peaceful life after all the chaos of the battle.
In some fanfictions, they might start a family right away. They could have a peaceful life at Hogwarts, with Harry perhaps teaching Defense Against the Dark Arts and Ginny coaching Quidditch. Their relationship would be stronger than ever, having survived the battle together.
They could discuss the losses they endured during the battle. Remembering friends and family who didn't make it. Ginny might talk about how she felt when she thought she could lose Harry forever. Harry could then comfort her and say that they have to move forward in their lives while keeping the memories of the fallen alive.
In many fanfictions, after the final battle, Harry might focus on rebuilding Hogwarts. He could use his influence to make it a more inclusive and modern place of magic learning, with new courses perhaps on Muggle technology and its integration with magic.
Their relationship could deepen with shared experiences of post - battle trauma. They support each other through the nightmares and flashbacks, which makes their bond stronger.
Well, their life after the battle in fanfiction could be full of new adventures too. Despite the end of the big battle, there could still be small threats or mysteries to solve. Ginny might continue her career in Quidditch while Harry could be involved in training new Aurors. And of course, they would have cozy evenings at home, sharing stories of their past with their kids.
After the battle in fanfiction, Harry's character may develop in a way that he starts to enjoy the simple pleasures of life. He no longer has the constant threat of Voldemort hanging over him. Ginny, who has always been brave, might now be seen as a source of stability for Harry. She helps him come to terms with his past and look forward to the future. Their relationship also helps them both to grow as individuals. For example, Harry might learn from Ginny's passion for Quidditch and become more involved in the sport as a spectator or supporter. Ginny might learn from Harry's sense of justice and become more involved in the wizarding community's political and social issues.