One plotline could be that Fenrir Greyback has been cursed to watch Hermione as a form of punishment or as part of a strange magical experiment. He initially hates the task but as he watches her, he becomes intrigued by her intelligence and courage. Hermione, on the other hand, notices his presence and tries to use her wits to either befriend him and break the curse or find a way to get rid of him. This could lead to a complex relationship where they are both enemies and yet have a strange connection due to the circumstances.
Well, perhaps in the fanfiction, Fenrir Greyback is under the command of Voldemort to watch Hermione as she is seen as a threat to the Dark Lord's plans. He might follow her around Hogwarts, observing her every move. This could lead to some tense moments where Hermione senses she's being watched but can't quite figure out who it is at first. As the story progresses, she could start to set traps to catch her stalker, which would be Greyback. And there could be a big showdown between them in the end.
One possible plotline could be that Fenrir takes Hermione as a hostage to use against the Order of the Phoenix. He might think that her connection to Harry Potter makes her a valuable bargaining chip. Another could be that he is under the control of a dark wizard who orders him to capture Hermione for some dark magic ritual. In some fanfictions, it could also be that Fenrir has some sort of personal vendetta against Hermione and takes her to exact revenge for something she did to him or his kind in the wizarding war.
One possibility is that it's a story of redemption for Fenrir. He starts to watch over Hermione and in the process, he begins to see the good in people he's been trying to harm. As he watches her, he might be influenced by her kindness or her intelligence, and this gradually changes his view of the wizarding world and his place in it.
It could be other Death Eaters. They might suspect that Fenrir is up to something with Hermione and try to stop him. For example, Bellatrix Lestrange could be a major antagonist. She's known for her cruelty and loyalty to Voldemort, and she might not trust Fenrir's actions regarding Hermione.
A possible plotline could be Hermione getting captured by Greyback's pack. She then has to use her wits and magic to escape. Maybe she befriends a young werewolf within the pack and uses that connection to her advantage.
One possible consequence could be her transformation into a werewolf. In many werewolf lore within the Harry Potter universe, a bite from a werewolf like Fenrir Greyback often leads to lycanthropy. This would mean that Hermione would have to deal with the monthly transformations, and she would likely face discrimination from some in the wizarding world who are prejudiced against werewolves.
One common plotline could be Hermione finding ways to outwit Fenrir Greyback. For example, she might use her intelligence and knowledge of magic to set traps or create diversions. Another could be other characters coming to Hermione's rescue, like Harry and Ron realizing she's in danger and using their skills to protect her from Greyback.
One possible theme is redemption. Maybe the fanfiction explores the idea of Greyback being redeemed through his interaction with Hermione. This could be appealing as it shows the power of goodness (represented by Hermione) over evil.
One possible plotline could be an alternate universe where Fenrir Greyback is redeemed early on. Maybe he has a moment of self - realization and decides to change his ways. He meets Hermione during this transformation process, and she initially distrusts him but gradually sees his efforts to become a better being. Their relationship could develop as she helps him fully embrace his new, non - violent self.
There's a fanfiction called 'Greyback's Redemption Arc'. In it, Fenrir Greyback saves Hermione from a group of Death Eaters. The author might have written it to explore the idea of redemption for a character like Greyback. Maybe he saves Hermione because he sees her as a symbol of the good in the wizarding world that he has lost touch with, and this act of saving her could be the start of his journey towards redemption.
In one fanfiction concept, Greyback saves Hermione when she is trapped in a magical maze created by dark wizards. Greyback, being a cunning and experienced dark creature, is able to navigate the maze and get to Hermione before the maze collapses or she is killed by the various traps inside. He might save her because he senses that she has a great potential that could be useful to him in the future.