Their relationship could be very different from what we expect. Maybe one is more interested in the dark arts while the other is more into the academic side of magic. So they could be constantly at odds about their future paths. But they also share a deep bond that only twins can understand, and they might communicate without words in some crucial situations.
Well, they could have a very complex relationship. On one hand, they might be extremely competitive, always trying to outdo each other in everything from academics to impressing their parents. Since they are in Slytherin, they could also team up and be a formidable duo, using their combined wits to get what they want in the wizarding world. Maybe they have a secret pact to protect each other no matter what.
The twin could change a lot. He might be the one who stops Draco from making some really bad decisions. For instance, if Draco was about to follow Voldemort's orders blindly, the twin could convince him otherwise. This would then change the whole course of Draco's actions and how he interacts with Harry Potter and his friends.
He could be resentful at first. After all, his parents have kept this big secret from him his whole life. But as he gets to know his twin, he might develop a sense of brotherly love. He may also start to question his family's values and actions in hiding his brother, which could lead to a change in his own character.
At first, it could be strained. Draco, being used to being the only son in the family's eyes, might feel threatened by his twin. He could be jealous if his twin shows more magical talent or is more popular at Hogwarts. But as they grow older, they might start to understand each other better. For example, if they face a common enemy, like a bully from another house, they could come together and realize the importance of family.
Self - discovery is also very common. Growing up as a Malfoy in the shadow of her brother, the sister often has to figure out who she really is. Is she just a Malfoy by name or does she have her own unique magic and personality? Fanfictions explore this by showing her journey, like learning new spells on her own or having a different view on the wizarding war than her family.
Their relationship would be a mix of rivalry and mutual respect. Draco might initially look down on Annabeth because she's not from his world, but Annabeth's strength and quick thinking would soon make him change his mind. They could have some heated arguments about the best way to do things, but deep down, they would care for each other as siblings. For example, Draco might use his magic to protect Annabeth when she's in danger in the wizarding world, and Annabeth would use her strategic skills to help Draco in his own battles.
At first, she may avoid Harry Potter altogether. However, if she discovers something that links her family's past to Harry in a way that she didn't expect, it could draw her closer to him. For example, if there was a hidden connection between the Malfoy family and Harry's parents. As she delves deeper into this connection, she might start to protect Harry from other Slytherins or even from her own brother at times. Their relationship could be one of mutual discovery and slowly - growing trust as they face the threats in the wizarding world together.
Often, he is used to create more complex family relationships. He might be caught between Draco's actions and his own beliefs. He could try to redeem the family name in some fanfictions, which adds a new layer to the Malfoy story. He may also be in a love triangle or have some other romantic entanglements that further complicate his character and the overall plot.
At first, they could be quite competitive. The older brother, having more experience and knowledge, might overshadow Draco. But as time goes on, they could grow closer. For instance, if the older brother gets into trouble, Draco could be the one to help him out, which would strengthen their bond.
One interesting aspect in Severus Snape and Draco Malfoy fanfiction is how Snape often acts as a mentor to Draco. Snape, being a complex character, has his own reasons for looking out for Draco. In many fanfictions, he tries to protect Draco from the darker aspects of the wizarding world that he himself has experienced. For example, he might shield Draco from the influence of Voldemort's more extreme followers. This relationship can be explored in different ways, such as through Snape teaching Draco some of his more advanced potions skills or giving him advice on how to deal with the politics within Hogwarts.
One popular Draco Malfoy twin sister fanfiction is 'The Malfoy Heir'. It delves into the unique relationship between Draco and his sister in the wizarding world. The story often shows how she navigates Hogwarts life, dealing with the Slytherin house politics and her own identity within the Malfoy family.