Fleur could be shown as more independent and brave. Since she's taking it upon herself to save Harry, it shows her courage. Maybe she becomes more confident in her own abilities outside of the Triwizard Tournament context.
Well, perhaps Fleur uses her Veela charm to intimidate the Dursleys into letting Harry go. She could arrive at Privet Drive in a blaze of magical beauty and power, and the Dursleys, being the cowards they are, would be too scared to oppose her when she demands Harry come with her.
Well, one possibility could be that Harry stumbles upon Fleur while she's being cornered by Death Eaters during a battle. He quickly uses a powerful disarming spell to take out the first Death Eater's wand. Then, he creates a diversion using a Patronus to confuse the rest and whisks Fleur away to safety.
In some fanfictions, Fleur might use her Veela charm to intimidate the Dursleys into letting Harry go. The Dursleys, being easily cowed by the extraordinary, would be no match for Fleur's alluring yet powerful presence.
Magic is essential in this scenario. Harry might have a special magical ability or connection that gives him an edge in saving Fleur. For instance, he could have a connection to the magic of the place where they are. If it's a forest, he could call upon the magic of the trees to help him. The trees could come alive and trap the Death Eaters, allowing Harry to rescue Fleur. This would show how in the wizarding world, magic is not just about spells from a wand but also about the connection to the surrounding magical environment.
In many fanfics, Fleur is often depicted as strong - willed. She's a Veela, so she has that alluring quality, but she's also smart and not just a pretty face. For example, in some fanfics she uses her Veela charm in a strategic way to get what she wants or to protect others.
Often, Luna Lovegood can be found in such fanfictions. Her unique and dreamy nature could bring a different dynamic to the harem. Neville Longbottom might also be involved in some way, perhaps as a friend who supports the harem and helps them out in times of need. There could also be some foreign exchange students or magical creatures in human form that end up in the harem for various reasons.
At first, their relationship might be a bit strained. Harry is used to his own space and friends, and Fleur has her own circle. But as they live together, they'll start to respect each other's differences. For example, Fleur might be more flamboyant in her magic use, while Harry is more practical. They'll start to see the value in each other's approaches and become closer friends.
Hermione would probably be a bit skeptical at first. She might worry that Harry is rushing into things. But once she sees how happy they are, she would be supportive. Ron, on the other hand, would be more accepting from the start, especially if there are good feasts at the wedding.
Often, Harry's sense of responsibility grows. He starts to see the marriage contract as not just a burden but also an opportunity to create a new life for himself and Fleur. Fleur's personality may develop in a way that she becomes more protective of Harry. For example, when they face opposition from the wizarding community about their contract, she stands up for them. She also might help Harry to overcome his insecurities about being in a relationship with someone as glamorous as her.