One possible plot twist could be that Harry discovers the marriage is part of a dark wizard's plan to gain control over him. Maybe the dark wizard wants to use Harry's fame and power within the wizarding world for their own evil deeds. Another twist could be that the person he is forced to marry is actually an undercover ally who is trying to protect Harry from a greater threat. For example, she might be pretending to be part of the forced marriage scheme but is actually working with Dumbledore's old network to keep Harry safe.
Maybe the forced marriage contract was set up by a well - meaning but misinformed wizard in the past. Harry initially resists but then realizes that the person he's supposed to marry has some crucial information about his parents. So, he decides to work with her within the bounds of the contract to uncover the secrets. And along the way, they actually start to develop real feelings for each other.
One interesting plot twist could be that the marriage is part of a dark wizard's plan to gain control over the wizarding world through Harry. But Harry discovers a hidden prophecy that gives him the power to turn the situation around and expose the dark wizard's true intentions.
Perhaps the bite leads to a rift between Harry and his friends. Some of his friends might be afraid of him now that he's a werewolf, while others might be over - protective. This could cause a lot of internal conflict within the group. Also, it could lead to Harry having to seek help from unexpected sources, like some of the more reclusive or misunderstood characters in the wizarding world who have experience with werewolves.
One possible plot twist could be that the 'forced slave' aspect is actually a ruse by Dumbledore to get Harry close enough to Voldemort to kill him. Harry discovers this later and has to deal with his feelings of betrayal. Another could be that when Harry kills Voldemort, he absorbs some of Voldemort's power and has to struggle with the dark side that comes with it. A third plot twist might be that the force controlling Harry as a slave is actually an ancient magic that has its own motives for wanting Voldemort dead, and Harry has to break free from this magic's control after killing Voldemort.
Well, a really interesting plot twist could be that when Voldemort controls Harry, Harry's personality starts to merge with Voldemort's in unexpected ways. For example, Harry might start to understand Voldemort's motives and see some truth in his views about the wizarding world, which creates an internal conflict for Harry. Another plot twist could be that the magic used to control Harry has a side - effect that it also starts to affect Voldemort's own magic in unforeseen ways. Maybe it makes Voldemort more vulnerable or changes his appearance. And there's always the chance that the control is not just a simple spell but a complex magical ritual that was set in motion long ago, and Harry has to figure out how to reverse the entire ritual to break free.
One interesting plot twist could be that they discover a hidden prophecy that states their union is the key to saving the wizarding world from a new, unknown threat. So, despite their initial resistance, they start to work together to fulfill this prophecy. Another could be that a powerful dark wizard has cast a spell on them, but as they try to break it, they actually start to understand each other better and form a real bond.
One possible plot twist could be that it's all a part of a dark wizard's plan to gain control over the wizarding world through their union. Maybe the dark wizard has some ancient magic that can be harnessed only if Harry and Ginny are married against their will. Another twist could be that it was a misinterpreted prophecy that led to this forced situation, and as they struggle against it, they discover new aspects of the prophecy that change everything.
A possible plot twist could be that the marriage contract was actually forged by a dark wizard to gain control over Harry. So, when they start to discover this, they have to fight against the dark wizard's plans while also dealing with their growing feelings for each other.
A plot twist could be that Albus is being blackmailed into kidnapping Harry. There could be a powerful dark wizard who has something over Albus, like the safety of another person Albus cares about. Another idea is that Albus has a wrong understanding of a magical prophecy. He thinks that by kidnapping Harry, he can prevent a great catastrophe, but in fact, he is misinterpreting the prophecy. Also, it might be that Albus has discovered some dark magic within Harry that he wants to contain, but his method of kidnapping is extreme and misunderstood by others.
A plot twist could be that Dumbledore faked his own death to test Harry's loyalty. But when Harry starts to turn on him, Dumbledore realizes his plan backfired. This would create a lot of tension and conflict between them, and also force Harry to re - evaluate his entire relationship with Dumbledore.