A possible plotline is that Lucius, having a crush on Hermione, starts to question his loyalty to Voldemort. His feelings for her make him realize the wrongness of the pure - blood ideology. Another interesting one could be that Hermione, being the smart one, figures out Lucius's crush and uses it to manipulate him into helping the Order of the Phoenix. And there could be a plotline where Lucius tries to court Hermione in his own, rather clumsy, way which leads to some really awkward and yet endearing moments.
Another plotline might involve a magical accident that causes Hermione to have a change in personality. This new, bolder Hermione starts flirting with Lucius out of curiosity and to see how the pure - blooded wizard will react. It could lead to some tense and interesting interactions between them.
Another plot could involve Lucius being under a spell or a curse that makes him look after Hermione. In this scenario, he might initially be reluctant but as time passes, he starts to genuinely care for her. He could introduce her to parts of the wizarding world that she hasn't seen before, like some ancient magical libraries or secret spells, all while still being conflicted about his new role.
In some fanfictions, Lucius might be forced into a situation where he has to rely on Hermione. For example, his family's fortune or status is at risk, and Hermione is the only one with the knowledge or skills to help. As he works with her, he discovers her many good qualities and becomes nice to her. This could lead to a whole series of events where they team up to face other threats in the wizarding world, all while their relationship evolves from one of necessity to one of mutual respect.
Perhaps there's a plot where Lucius Malfoy is in a situation where he owes Hermione a debt. This could lead to a strange relationship where he has to follow her around and protect her. As time passes, he starts to develop unexpected feelings for her.
Another plot is a sort of forbidden love story. Given their different allegiances in the original series, a fanfiction might explore how Hermione and Lucius overcome their differences and fall in love. It could involve a lot of tension, secrecy, and internal conflict as they deal with their feelings and the reactions of the wizarding community.
One possible plotline could be that Hermione is magically bound to Lucius in some way during a complex spell gone wrong. This forces them to interact and gradually, she discovers a different side of him that she's attracted to. For example, he might show kindness towards a house - elf in front of her, which challenges her pre - conceived notions of him.
One interesting plotline could be the clash of their different ideologies. Hermione, with her strong beliefs in equality and justice, and Lucius, from a traditional pure - blood family with elitist views. Their marriage, forced by the law, might lead to a power struggle within the Malfoy household as Hermione tries to assert her values.
Maybe Lucius has a secret admiration for Hermione's tenacity. In a plotline, he could be under a curse that makes him see the good in those he once despised. This leads to him being charming towards Hermione. She, in turn, is initially suspicious but gradually starts to question her own views of him as he continues to be kind and helpful in unexpected ways.
Perhaps in a post - war scenario, Hermione is working on reforming the wizarding laws. Lucius, who has lost much of his power and status, is begrudgingly involved in the process. Through a series of debates and interactions, they develop an unexpected connection that challenges their long - held beliefs about each other.
One possible plotline could be that Lucius realizes Hermione's importance in the wizarding world's future. Maybe he discovers a prophecy that involves her and decides to protect her from the dark forces that also threaten his own family. Another could be that Hermione somehow saves Lucius' son Draco from a dangerous situation, and out of gratitude, Lucius feels compelled to protect her.