What could be the plot of a fanfiction where Harry is in a contract with Voldemort?

One possible plot could be that they are forced to join Voldemort under some sort of dark magic compulsion. Maybe Voldemort has a new powerful spell that he uses on them to make them his servants. Then they have to struggle with their own moral compasses while doing his bidding, and secretly try to find a way to break free and defeat him from the inside.

One possible plot could be that Harry is magically transformed into a panther by Voldemort as a form of punishment or control. Harry, in his panther form, has to find a way to break the spell while also trying to gather information about Voldemort's plans. He might use his new form's abilities, like stealth and speed, to his advantage.

Well, it could be that Voldemort has a strange fascination with wolves and decides to turn Harry into one as part of his plan to create a super - being under his command. Harry, in his wolf form, retains his own consciousness and memories. He has to endure the instincts of the wolf while also plotting against Voldemort. He might use the wolf's enhanced senses to gather information about Voldemort's lair and his plans, all while pretending to be under Voldemort's control.

One possibility could be that Voldemort rescues Harry Potter for some self - serving reason. Maybe he realizes that Harry holds the key to a greater power that he wants to obtain. So, instead of killing Harry, he saves him from another threat, like a powerful dark wizard who is trying to overthrow Voldemort and sees Harry as a useful tool as well. In this fanfiction, Harry would be in a very strange situation, having to trust Voldemort at least temporarily.

One possible plot could be that they are forced to be partners to save the wizarding world from an even greater threat. Maybe an ancient evil that neither of them can face alone. So, they have to put aside their differences and work together, which would be a huge change from their usual enmity.

In a 'harry joins voldemort fanfiction', perhaps Harry discovers a dark secret about the wizarding world that makes him think Voldemort was right all along. It could be something about the Ministry of Magic being corrupt and Voldemort's way of ruling, although extreme, is the only solution. So he joins Voldemort to 'fix' the wizarding world.

Perhaps Dumbledore is being forced in this fanfiction. There could be some dark magic or powerful dark wizard threatening Hogwarts or the wizarding world. Dumbledore, in a desperate attempt to save everyone else, gives Harry to Voldemort as a sacrifice. But Harry, being the hero he is, could find a way to turn the situation around and defeat Voldemort from within his lair.

One possible plot could be that Harry, being Voldemort's little brother, has been hidden away from the wizarding world by some powerful magic. As he grows up, he starts to discover his true identity and his connection to Voldemort. This discovery throws the wizarding world into chaos as they don't know whether to trust Harry or see him as a threat.

One possible plot could be that Harry discovers a prophecy that ties his and Voldemort's fates together in a more intimate way than just being enemies. This leads him to seek out Voldemort to understand it better. As they interact, they find themselves attracted to each other. Voldemort, who has always been alone in his pursuit of power, starts to question his motives, and Harry tries to convince him to turn away from the dark path. The plot would be filled with internal and external conflicts as they navigate their relationship and the consequences it has on the wizarding world.

One possible plot could be that Harry discovers some sort of ancient magic or prophecy that links him to Voldemort and Lucius in a way that makes them mates. This could lead to a struggle within Harry as he tries to come to terms with his new identity and the expectations that come with it.