Maybe Harry steals Hermione's Time - Turner because he has some desperate plan to go back in time and fix a big mistake. For example, he might want to prevent the death of a loved one, like Sirius. He could think that Hermione's Time - Turner is his only chance to do so.
In this fanfiction, perhaps Harry steals the Time - Turner as part of a plot by an enemy who has somehow influenced or possessed him. This would create a complex situation where Hermione not only has to retrieve the Time - Turner but also has to figure out how to free Harry from this control. She might have to team up with Ron or other characters to solve this problem and set things right in both the present and any disrupted timelines.
Well, it could be that in the fanfiction, there's some sort of misunderstanding or dark influence on Harry. He might steal the Time - Turner without fully realizing the consequences. And Hermione would be really angry and confused, then she'd have to go on a quest to get it back from Harry while also dealing with the potential time - related chaos that Harry might have caused.
She would be furious. The Time - Turner is her precious possession, and Harry stealing it would be a huge betrayal in her eyes.
Perhaps in this fanfiction, the Time - Turner malfunctions while Hermione is in the middle of a confrontation with Bellatrix. This could send them both to a different time period, maybe even one where the wizarding world is in a completely different state. They would have to find a way to work together, at least temporarily, to get back to their own time. Hermione would be reluctant to trust Bellatrix, but she might not have a choice. And Bellatrix would be both intrigued and suspicious of Hermione.
Well, it could be that Draco steals Harry's glasses as a prank. Maybe he wants to embarrass Harry in front of their classmates. He might hide the glasses in a secret place in Hogwarts, like in an old unused classroom, and Harry has to search for them while dealing with his blurry vision.
The plot could start with Harry realizing he has deeper feelings for Hermione than just friendship. He might start spending more time with her, which causes tension between him and Ron. Eventually, he could confess his feelings to Hermione, and she might be conflicted because of her relationship with Ron.
One interesting plot could be that they use the Time Turner to prevent a major disaster at Hogwarts that was overlooked in the original story. For example, they might stop a dark wizard from infiltrating the school during an important event.
One possible reason could be that she is in a desperate situation. Maybe she needs something for a very important spell or potion to save someone's life and she thinks Harry won't notice or will forgive her. For example, if there is a rare ingredient that only Harry has access to and time is running out.
One great 'Time Turner Hermione' fanfiction is 'Hermione's Time - Turner Adventure'. It delves into Hermione using the Time Turner for more than just attending classes. The story is full of mystery and her character development is really interesting as she faces new challenges.
One common storyline is Hermione using the Time Turner to prevent a major disaster in the wizarding world. She might go back in time to stop a dark wizard from getting a powerful artifact.
One idea could be that Hermione accidentally travels too far back in time with the Time - Turner and ends up in Severus' student days. She has to navigate Hogwarts without being detected while also trying to figure out how to get back. And Severus stumbles upon her and at first is suspicious but then realizes she's from the future and they start to work together to fix the time - line.
One idea could be that Hermione, using the Time - Turner, accidentally goes back to a time when Lucius was a young Death Eater in training. She tries to subtly change his path, which leads to a series of events where they form an unlikely alliance. They might start to understand each other's motives and values more deeply.