Another theme is the exploration of complex relationships. Since they were enemies in the original series, in mature fanfiction, their relationship becomes more than just hatred. It could be a reluctant friendship that slowly turns into something more, like in 'A Thin Line' where they start to understand each other on a deeper level over time.
Love and acceptance are also key themes. As they grow up, they come to terms with their feelings for each other, whether it's platonic or romantic love. In 'Changing of the Guard', the story shows how they learn to accept each other's flaws and grow together in a world that still has some prejudices against their relationship.
One common theme is redemption. Draco is often depicted as having a chance at redemption through his relationship with Harry. For example, in many stories, Draco realizes the error of his ways under Voldemort's influence and Harry helps him turn a new leaf.
One common theme is self - discovery. As they are older, Harry and Hermione are often portrayed as exploring more about themselves outside of their Hogwarts personas. Another theme is love in a more mature sense, not just the puppy love of their younger days but a deeper, more complex kind of love.
Another theme is the power of love to overcome differences. Hermione and Draco come from very different backgrounds and have opposing beliefs in the original story. But in fanfiction, their love (whether it's romantic or a deep friendship) is often shown as something that can bridge these gaps. They learn to accept each other's flaws and differences. For instance, in some stories, they work together to fight against a common enemy which makes them see each other in a new way.
Another theme is the exploration of the wizarding world's prejudice. Since it's a gay relationship in a magical world, the fanfictions often deal with how the wizarding society might react to such a relationship. For example, they might face opposition from some pure - blood families or Hogwarts faculty. It shows how Harry and Draco have to fight against these prejudices to be together.
One common theme is rivalry. Harry's squinting at Draco can be seen as part of their ongoing rivalry at Hogwarts. Another theme is mystery. Draco often has secrets, and Harry's squinting might be his way of trying to figure them out.
One common theme is redemption. Draco is often shown on a path of redeeming himself in the eyes of Harry and others. Another theme is friendship turned into something more. Their initial enmity slowly evolves into a deeper connection.
One common theme is redemption. Many fanfictions explore Draco's journey towards redemption and how Harry can play a part in it. For example, Draco realizing the error of his ways under the influence of Harry's more noble values.
The power of forgiveness also pops up a lot. Harry, being the hero he is, often has to grapple with whether to forgive Draco for all the mean things he's done in the past. And this struggle and the ultimate act of forgiveness (or not) can be a major part of the story. Fanfictions might explore how this impacts their relationship and the wizarding world around them.
One common theme is family loyalty. Since they are brothers, the fics often explore how they deal with their loyalty to each other and their family. Another is identity, as Harry's identity as a Potter and now also a Malfoy would be in question.
The theme of loyalty also pops up a lot. They are Slytherins, so loyalty to their house and to each other is a big part of these stories. Sometimes they have to make difficult choices that test their loyalty, like when faced with the actions of other Slytherins or the wider wizarding conflict. These loyalty - based plotlines can create some really intense and engaging stories.