One possibility is that Bellatrix would try to escape and Harry would be there to stop her. This could lead to intense magical battles within the prison walls. Harry, with his strong sense of justice, would not allow her to break free and continue to cause chaos. Meanwhile, Bellatrix, being the deranged Death Eater she is, would stop at nothing to get out and might even try to use Harry as a hostage or a bargaining chip.
One possibility is that it could be a story of redemption for Bellatrix. Maybe Harry, in his ever - empathetic nature, tries to understand what led Bellatrix to become so evil while they are both in Azkaban. He might try to reach out to the part of her that was once good, perhaps influenced by the idea that everyone has some good in them.
The plot could revolve around Bellatrix's memories in Azkaban. Since she was there for a long time, she might have had some extremely vivid and disturbing memories. A fanfiction could explore these memories and how they influenced her actions after she escaped. For example, she might have seen the faces of those she killed in her dreams while in Azkaban, and this could have made her more vengeful.
One possible fanfiction could be about Bellatrix's time in Azkaban and how she coped with the Dementors. Maybe she had some hidden magic that she used to keep her sanity in that dark place. It could also explore her thoughts about Voldemort during her imprisonment and how her loyalty to him remained unshaken.
A plot twist could be that the Dementors in Azkaban are not what they seem. Harry and Bellatrix find out that they are being controlled by a greater, more sinister force. This discovery makes them put aside their differences and fight together against this new threat, which is something no one would expect considering their prior relationship.
One thing that could happen is that the wizarding world would be in chaos. The Death Eaters would be confused by Bellatrix's actions, and the Order of the Phoenix would be very suspicious. Harry would be in a difficult position, not knowing whether to trust Bellatrix or not.
In fanfiction, Bellatrix might try to capture Harry on the spot. She's a Death Eater and Harry is her enemy. She could use dark magic spells to try and subdue him.
In a Harry Potter fanfiction where Bellatrix Lestrange joins, she could be a major source of conflict. She's extremely skilled in the Dark Arts. Her addition to the story might see her influencing the plot in ways that are both unpredictable and dangerous. For instance, she could manipulate other characters, especially those on the darker side of the wizarding world. She might also introduce new magical elements or artifacts that are related to the Dark Arts. Her character is so complex and unpredictable that she could either be a pure antagonist or, in a more creative take, have a change of heart and become an anti - hero, but this would require a very well - written and thought - out plot.
If Harry is sent to Azkaban in fanfiction, it would be a huge shock to the wizarding world. In Azkaban, the dark and gloomy environment would take a toll on him. But Harry has a strong will, so he might try to resist the effects of the Dementors. His Gryffindor courage would be put to the ultimate test. And he may discover some secrets about Azkaban while he's there, which could lead to a whole new plotline in the fanfiction.
Well, in some fanfiction scenarios, Snape might rescue Harry from Azkaban because he discovers new evidence that clears Harry's name. Maybe he uncovers a dark plot by some other powerful wizard who framed Harry, and his sense of justice, despite his past animosity towards Harry, drives him to act.
If Harry Potter were sent to Azkaban in fanfiction, it could be a very dark turn of events. He would likely be wrongly accused, as he often is in the face of Ministry corruption. His time in prison might involve him using his magic in secret to resist the Dementors, and it could also lead to an uprising within Azkaban by other inmates who believe in his innocence. It could also prompt his friends to stage a dangerous rescue mission.