Sometimes, the fight can be about a misunderstanding. Like when Draco thinks Harry has stolen something from him or has wronged his family in some way. Their fight then becomes a way to clear the air and resolve the misunderstanding, often with some help from their friends along the way.
One common plotline is a magical duel over a school competition. Maybe it's for the House Cup, and their fight gets intense as they both use their unique spells. For example, Harry might use his Patronus charm while Draco counters with some dark - arts - inspired hexes.
One interesting plotline could be that they discover their twin relationship early on and try to keep it a secret from everyone at Hogwarts. They might secretly help each other out in classes and with their rivalries against other houses.
A great plotline might involve a magical competition where Draco, Blaise, and Harry are all forced to compete. As they face various challenges, they start to understand each other better. For example, they realize that they all have the same fears about the future of the wizarding world. It could also be a plotline where they are all transported to an alternate dimension and have to rely on each other to get back home.
One interesting plotline could be Harry and Draco being deaged and having to rely on each other in a world that seems new to them again. They might form an unexpected friendship as they don't have the pre - conceived notions from their older selves. For example, they could team up to solve a mystery in Hogwarts that only they, with their combined knowledge from before, can figure out.
Well, in some 'Draco Adopts Harry' fanfictions, a great plotline is how Draco overcomes his past enmity towards Harry. He starts to see Harry as a person in need rather than an enemy. There could be a plot where they work together to uncover secrets about Harry's past that Dumbledore might have hidden. And then, Draco has to protect Harry from those who don't want the truth to come out.
Perhaps a plot where they all become animagi and have to use their animal forms to solve a mystery in the Forbidden Forest. Draco as a sleek snake, Harry as a stag, and Hermione as an otter, they must navigate the forest's dangers and uncover the truth about a strange magical disturbance.
A great plotline is when they bond over their difficult family situations. Harry has his issues with the Dursleys and Draco has the pressure from his pure - blood supremacist family. They could find common ground in their struggles against the expectations placed on them. This might lead them to support each other in ways that surprise their classmates and teachers alike, like Draco standing up for Harry against Snape's unfair treatment, or Harry helping Draco break free from his family's dark influence.
One interesting plotline could be them learning to get along despite their past rivalries. For example, they might start to understand each other's insecurities and fears. Another could be them teaming up against a common threat in the wizarding world while living together, which forces them to trust each other. And there could also be a plotline where they discover new magical things together in their shared living space.
Perhaps the fanfiction explores how Harry's new role as Draco's bearer changes their relationship dynamic. It could start with them being enemies as they were in the original series, but as Harry takes on this role, they gradually start to understand each other better. For example, they might find common ground in their struggles against the expectations of their families.
One possible plotline could be that Harry, in a strange magical turn of events, is transformed into a small animal and Draco finds him. Draco then decides to keep him as a pet. Another could be that it's all part of a secret spell experiment where Draco has to take care of Harry in pet form to learn about empathy.
One interesting plotline could be how Harry and Draco initially react to the marriage contract. Harry might be shocked and resistant as he has always seen Draco as an adversary. Draco, on the other hand, might be more accepting due to his family's traditional views. Another plotline could involve them trying to keep the contract a secret from their friends and Hogwarts community, which would lead to some comical and tense situations.