Perhaps they start to see each other in a new light. In the past, they can observe their younger selves and how they interacted. This new perspective might make them appreciate their relationship even more. For example, Harry could see how Ginny was always there for him, even when he didn't notice in his younger days. Ginny could also see how Harry was growing and maturing, which makes her love him more deeply.
It could become stronger. As they face the challenges of the past together, they rely on each other more. They might share their future experiences, which deepens their understanding of one another.
It often starts with a growing attraction. Harry begins to notice Ginny in a new light, seeing her not just as Ron's sister but as a strong and independent witch. Ginny, on the other hand, has had a crush on Harry for a long time and now that they're dating, she shows him different parts of Hogwarts that he might not have known before.
In the fanfiction, their relationship could develop through shared experiences. When they work together, they discover new things about each other. Maybe Ginny has a hidden talent for potion - making that Harry didn't know about, and this new discovery makes him see her in a different light, strengthening their bond.
In some fanfictions, their relationship deepens as they rely on each other more during the dangerous times of the Deathly Hallows. They might share more intimate moments of fear and hope, which bring them closer together.
It often develops slowly. At first, they might just exchange glances that hold a hidden meaning. Then, they start to find excuses to be near each other more often.
If they travel back to a time when Ginny was much younger, like when she was a first - year and Harry was a bit older (due to time travel), Harry could become a sort of protector and mentor to her. This would build a different kind of bond. He could help her discover her magic in new ways and she could show him the innocence and wonder of Hogwarts from a young student's perspective. As she grows older in that time period, their relationship could shift from mentor - mentee to a more romantic one in a very unique way.
Their relationship might develop more deeply. They have both been through a lot during the war, and this shared experience could bring them closer. They would start to understand each other on a whole new level. For example, Harry might see Ginny's strength in a different way, and Ginny would see Harry's vulnerability more clearly. This new understanding would strengthen their bond.
In some fanfictions, they might have a bit of a rough start. Maybe Harry has some post - war trauma that makes it difficult for him to fully open up at first. But Ginny, being strong - willed, helps him through it and their relationship deepens as a result. They learn more about each other's dreams and fears outside of the Hogwarts environment. They could start to realize that they want to be more than just boyfriend and girlfriend, but true life partners in all aspects of the wizarding world.
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.
Often, the battle intensifies their relationship. They rely on each other more than ever. The shared danger makes them more aware of their feelings. For example, a near - miss from a dark spell might make them realize how much they can't bear to lose each other.
The Room of Requirement can be a place of shared adventures for them. As they explore the ever - changing room together, they rely on each other's skills and strengths. This mutual dependence makes their relationship grow. For example, if they face a dangerous magical creature in a part of the room, they work together to defeat it, and this shared experience brings them closer. It also gives them a chance to be themselves without the expectations of others around them at Hogwarts.