Often, there could be a threat from dark forces, like Death Eaters, and Fleur uses her Veela powers to shield Harry. For example, she might sense danger before Harry does and step in to prevent him from being attacked.
In some stories, there may be a situation where Harry is being unfairly judged or targeted within the wizarding community. Fleur, having a strong sense of justice, becomes protective. She may stand up for Harry in front of the Ministry of Magic or other powerful wizards, using her charm and intelligence to make her point.
Often, the plotlines involve Fleur helping Harry in some way, like during a dangerous situation. Maybe it's a battle where she uses her skills as a Triwizard champion to protect Harry, and through that shared experience, her crush deepens. There are also fanfics where Fleur has to hide her feelings because of her family's expectations or because she's worried about Harry not reciprocating. This leads to some angsty moments where she's torn between her feelings and what she thinks she should do.
One interesting plotline could be the cultural clashes between the two families during the wedding preparations. For example, Fleur's French heritage might bring in different wedding traditions that Harry's friends and family find strange or exciting. Another could be the role of magic in the wedding decor. Maybe there are enchanted flowers that change colors or float in the air. Also, the reactions of the guests, like Hermione's thoughts on the whole event, could be a great part of the story.
One possible plotline could be that it's set after the war. Harry and Fleur find solace in each other's company. They might be sitting by the fireplace in the Burrow, and as they cuddle, they share stories of their past traumas. Fleur could talk about how difficult it was for her being part - Veela during the war, with people being both attracted and distrustful of her. Harry, in turn, would open up about his experiences with Voldemort. Their cuddling becomes a source of comfort and a sign of a new beginning for both of them.
Well, a common plotline is the development of relationships within the harem. For example, Harry might initially be a bit hesitant about the whole harem concept, but as he gets to know Fleur and the other potential members, he starts to embrace it. There could also be a plot where they are all on a quest to discover some ancient magic, and during this journey, their bonds in the harem become deeper and more complex.
One interesting plotline could be how Harry and Fleur adjust to their betrothal. Maybe they start off as strangers and gradually learn about each other's likes and dislikes. Another could be the reactions of their friends, like Ron might be jealous at first or Hermione might be a bit skeptical but then come around.
Another option is to check out some dedicated Harry Potter fanfiction forums. These forums usually have sections for different themes and relationships in fanfiction. Look for threads or topics related to Fleur being protective of Harry. Some users may have bookmarked or recommended such fictions in those areas.
The theme of cultural differences also often appears. Fleur being part - Veela and from a different wizarding culture than Harry adds a layer of complexity. Their interactions can involve misunderstandings at first but then growth as they learn about each other's cultures.
The theme of unexpected love also pops up a lot. Given that in the original series, there's no real indication of a relationship between them, fanfiction writers like to explore how they might fall in love. It could start from a simple friendship or a shared experience that suddenly makes them see each other in a new way.
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.
One possible plotline could be Harry helping Fleur out of a dangerous situation, which creates the life debt. Then, Fleur might feel obligated to protect Harry in return, leading to adventures where they face dark wizards together.