Perhaps Fleur is being controlled or influenced by a dark force. In the Harry Potter universe, there are many dark magic entities that could manipulate someone into kidnapping Harry. It could be that she is under the Imperius Curse or some other form of mind control. Another reason could be that she has some sort of personal vendetta against Harry or those close to him, and kidnapping him is her way of getting revenge. She might think that Harry has wronged her in some way, whether it's real or just in her deluded perception.
In a 'fleur kidnaps harry fanfic', Fleur might kidnap Harry out of love in a very twisted way. Maybe she loves Harry but he doesn't return her feelings, so she decides to take matters into her own hands. By kidnapping him, she hopes to make him see her in a different light or to be close to him against his will. It could also be related to some sort of prophecy or magical prediction that she believes involves Harry and she wants to ensure that she is part of it by taking him hostage.
Maybe Fleur has some ulterior motive. She could be under the influence of a dark wizard who forces her to kidnap Harry. Or perhaps she believes Harry has something she needs desperately, like a powerful magical item that she thinks can save her family or something.
Yes, there might be such fanfics out there. Fanfic writers often come up with all sorts of creative and sometimes out - of - the - box scenarios. You can try searching on popular fanfic websites like Fanfiction.net or Archive of Our Own. Just type in the title keywords and see what pops up.
One possible plot could be that Fleur has been influenced by some dark magic or a powerful enemy. Maybe she's being blackmailed to kidnap Harry. She might take him to a hidden location, perhaps an old, abandoned castle. Then, the story could revolve around Harry trying to figure out why Fleur did this and how to escape while also dealing with Fleur's internal struggle about what she's done.
One possible motive could be his obsession with Will. Hannibal sees Will as a unique individual, almost like a kindred spirit in some ways. He might kidnap Will to have him all to himself, away from the outside world that he believes corrupts or misunderstands Will.
In a 'Harry framed Dumbledore' fanfic, a motive could be revenge. Suppose Dumbledore made a decision that Harry thought was wrong and cost someone Harry loved dearly. Harry could then be driven by revenge to frame him. Also, it could be a case of Harry being under the influence of a dark force. The dark force might convince Harry that Dumbledore is a threat and needs to be removed from power, leading Harry to frame him.
It could be that Naruto has lost his sanity temporarily. The stress of being a hero, the constant battles, and the losses he has endured might have taken a toll on his mental state. In this state of instability, he may see Sakura as a symbol of something he wants to preserve or protect, but his way of doing so is through kidnapping. Or there could be a new villain in the story who has the ability to make Naruto act out of character, and this villain's plan involves Naruto kidnapping Sakura.
One possible motive could be jealousy. Maybe the kidnapper woman is jealous of the saleswoman's success or the attention she gets from customers. Another motive might be related to a personal grudge. For example, the saleswoman might have unknowingly offended the kidnapper in the past. It could also be a case of misinformation. Perhaps the kidnapper has been wrongly informed that the saleswoman has something she wants, like a valuable item or some important information.
It could also be for revenge. Perhaps Stiles or someone associated with him has wronged Peter in the past within the context of the fanfiction story. So, Peter kidnaps Stiles to get back at him or those related to him. Another reason might be that Peter is being controlled by some other force. There could be a dark entity manipulating Peter's actions, and it makes him kidnap Stiles for its own sinister purposes.
I haven't come across such a 'fleur kidnaps harry fanfic' directly. However, if you join some Harry Potter fanfic communities on platforms like Reddit or Discord, you could ask the members there. They are often very knowledgeable about various fanfic scenarios and might be able to point you to the right ones.
In one plotline, Fleur could be the target of a curse that slowly drains her magic. Harry, as her bodyguard, has to find a way to break the curse while keeping her safe from those who might want to take advantage of her weakened state. This could involve seeking out ancient spells and potions, and they might have to journey to dangerous and mysterious places. As they do so, their relationship could evolve from Harry simply being a protector to someone Fleur deeply trusts and relies on, and there could be hints of a romantic connection developing between them.