Well, in some fanfictions, Draco might realize the error of his ways. Maybe he starts to see the Golden Trio's true qualities, like Harry's courage, Hermione's intelligence and Ron's loyalty. This new understanding could lead to the start of a friendship.
Perhaps a plot twist where Draco sacrifices himself for the Golden Trio. In a moment of danger, instead of saving himself as one might expect from his Slytherin self - preservation instincts, he chooses to protect his new friends. This would be a huge shock and a great development in the story of their friendship. It could also lead to the Trio then finding a way to bring Draco back to life, which would be another interesting turn in the plot.
Perhaps a mutual friend like Hermione could play a role. She might set up a situation where Draco and Harry have to work together on a project. At first, they would be reluctant, but as they start to see each other's positive qualities, like Draco's determination and Harry's loyalty, they begin to respect each other and a friendship could form.
One possible storyline could be about the trio's efforts in rebuilding Hogwarts. They might use their magic to restore the damaged parts of the school, and also deal with the memories left behind by the war. For example, Neville could be helping them in the Herbology department, which was probably in a mess after the battle.
Often, their friendship is shown as a secret at first. Hermione, being friends with a Slytherin like Draco, would face opposition from her Gryffindor friends. But as they spend time together, they find common interests in things like advanced magic theory or ancient runes. This mutual interest cements their friendship over time.
Yes, it is possible. In some fanfictions, they overcome their differences. Maybe they find out they have more in common than they thought, like their love for Quidditch or the pressure they face from their families.
It changes it a great deal. Firstly, the group dynamic becomes more complex. The Golden Trio was initially based on friendship and a common goal against Voldemort. With Draco in it, there could be more internal conflict at first as his background and beliefs are different. However, over time, it could add a new layer of depth. His family connections might provide different resources or insights that the original trio didn't have. And it can lead to some really unique storylines where they all have to learn to trust each other despite their differences.
In a Hogwarts setting, their friendship could start gradually. Maybe they get paired up for a difficult project in Potions. At first, they're both hesitant and a bit hostile, but as they work together, they realize they have more in common than they thought. Hermione's thirst for knowledge and Draco's cunning could combine in interesting ways to solve the project's challenges. This shared experience could be the first step in breaking down the barriers between them.
The Malfoy family's reputation would take a big hit among the pure - blood families. Many of them would see Lucius as a traitor for befriending Harry. But some of the more open - minded pure - bloods might start to think differently. As for the Gryffindors, some would follow Ron's lead and be hostile, while others, like Neville, might be more open to the idea. After all, Neville has also seen the good in people who were once considered enemies.
In many fanfictions, their friendship changes their social interactions. Harry was always surrounded by his Gryffindor friends, but with Draco as a friend, he starts to interact more with Slytherins. Draco, who was used to being with his Slytherin clique, now has to deal with Harry's Gryffindor friends. This new dynamic forces them both to step out of their comfort zones. It also makes them more adaptable. They learn to handle different situations and people better because of their friendship.
Hermione could become more understanding of the grey areas in life. Draco's complex family situation and his own internal struggles would show her that things are not always black and white. For Draco, his friendship with Hermione might make him more self - reflective. He would constantly compare his actions and beliefs to Hermione's, and this would lead to a transformation in his character. He would gradually move away from his arrogant and elitist ways as he realizes the value of true friendship and equality.