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.
Another possible plotline is the development of an unexpected emotional connection between Hermione and Lucius. At first, they may despise each other due to their differences. But as they are forced to live together, they start to understand each other's past traumas and insecurities. This could lead to a slow - burning romance that defies the expectations of both the wizarding world and the readers.
In some fanfictions, the plot could revolve around Hermione using the marriage law situation to her advantage. She might see it as an opportunity to infiltrate the pure - blood society and change it from within. With Lucius as her reluctant husband, she could start to reform the Malfoy family's views on blood purity and wizard - muggle relations.
Hermione could also use her magic skills to her advantage. She is a powerful witch, and in the Malfoy household, she may use her magic to create a space for herself where she can be true to herself. She might also use magic to subtly influence Lucius and make him more accepting of her and her beliefs.
Well, sometimes in these fanfictions, a common plot is that Hermione and Lucius are forced into the marriage by the law at first. But as time goes on, they start to discover unexpected similarities in their love for knowledge. For example, Hermione's thirst for magic knowledge and Lucius' in - depth understanding of the dark arts (not in an evil way but in a historical and academic sense). They might then team up to solve some magical mystery together, which not only brings them closer but also changes their relationship dynamic completely.
One possible plot twist could be that the marriage law is part of a political ploy. Maybe the wizarding government wants to unite the pure - blood and Muggle - born factions through this law. Hermione, being the strong - willed character she is, initially resists but then realizes she can use this situation to advocate for better Muggle - born rights within the pure - blood society. Lucius, on the other hand, has his own motives, perhaps trying to regain some of his lost status in the wizarding world by being seen as more 'open - minded' through this marriage.
Their relationship could develop in a rather complex way. Given their very different backgrounds, there would be a lot of clashes. However, the marriage law forces them to coexist. As time passes, they might find common ground in their love for the wizarding world, albeit from different perspectives. Hermione could introduce Lucius to the idea of a more inclusive wizarding society, and Lucius could teach Hermione about the long - standing pure - blood traditions that have some value, if reformed. This mutual exchange could lead to a grudging respect and eventually something more like friendship or even love.
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.
One possible plotline could be Lucius having a change of heart due to Hermione's intelligence and strong will. Maybe he starts to question his Death Eater beliefs as he interacts with her at Grimmauld Place. Another could be Hermione using her knowledge to outwit Lucius in some sort of magical duel or intellectual battle within the house.
One plotline could be Hermione discovers a hidden prophecy that involves Snape and Lucius. Another is that Snape has to protect Hermione from Lucius' dark plans. Or maybe Hermione is a mediator between Snape and Lucius in a magical conflict.
Another plotline could involve the other characters' reactions. Harry and Ron might go on a rescue mission. They would face various challenges while trying to find Hermione and Lucius. They could encounter Lucius' Death Eater allies and have to fight them off.
For Hermione, it's about her growing in a new and often hostile environment. She has to deal with the pure - blood elitism which she has always opposed. This forces her to become more diplomatic while still holding onto her values. Lucius, on the other hand, has to re - evaluate his beliefs about muggle - borns. His character develops as he sees Hermione's intelligence and strength, which makes him question his former bigotry.
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.