A necklace can be a physical symbol of their connection. It can be a conduit for magic that links their minds or emotions. For instance, it could allow them to communicate telepathically.
The necklace could also be a representation of a cultural or magical heritage that is important to both Hermione and Draco's families. If it has a long and mysterious history, it can draw them together as they try to understand its significance. Maybe it was created during a time when Gryffindors and Slytherins worked together in the past, and now it's a sign that they should do the same in the present. Their exploration of the necklace's story can be a way to bridge the gap between their two houses and their own personal differences.
Some fanfictions might use the snake necklace as a sign of danger or a connection to the Dark Arts. Draco could be in possession of it, and Hermione, being the brave and intelligent witch she is, tries to understand its power in order to protect Hogwarts or even Draco himself from the possible negative influences associated with the necklace.
The collar could be a symbol of power. For example, if it's a rare magical item, it might give Draco an edge in battles or in the wizarding world's power struggles.
The snake necklace can also drive the relationship between Hermione and Draco. Say Draco has lost the snake necklace and Hermione finds it. He might be angry at first, thinking she stole it. But as they interact more to resolve the misunderstanding, they start to see each other in a new light. It's like a MacGuffin that moves their relationship forward in the fanfiction.
In some fanfictions, the snake necklace could be a symbol of Draco's Slytherin heritage. It might be used to show his connection to the darker, more mysterious side of the wizarding world. Hermione's interaction with it could represent her delving into that part of Draco's world, perhaps as a way to understand him better or to bridge the gap between Gryffindor and Slytherin. For example, if Draco gives Hermione the snake necklace in a fanfic, it could be a sign of his trust or a new level of their relationship.
They might interact with fear at first. Draco, if he becomes a werewolf - like, could be feared by Hermione due to the common perception of werewolves. But as the story progresses, she could overcome that fear and try to understand his situation better.
In certain fanfictions, the snake necklace is enchanted. It could have powers that only Hermione can unlock. This then leads to a series of adventures where she and Draco have to work together. For instance, the necklace might open a secret passageway in Hogwarts that was created by an old Slytherin wizard, and they need to explore it for some important reason like finding a lost magical artifact.
She could stand up to him. Hermione is known for her intelligence and quick - wittedness. So she might use her sharp tongue and logical arguments to put Draco in his place. For example, she could expose his wrongdoings or the flaws in his pure - blood ideology.
The werewolf element can make their relationship more complex. For example, if Draco is a werewolf, Hermione might have to deal with the prejudice against werewolves while being with him. Or if Hermione is involved in werewolf research and Draco has a family history related to werewolves, it can create a new level of understanding and conflict between them.
There might be a fanfiction where the necklace has a hidden prophecy related to Hermione and Draco. As they discover the secrets of the necklace, they are forced to work together. Along the way, they realize that the connection through the necklace is not just about the prophecy but also about their shared destiny in the wizarding world. This could involve them facing various dark forces while being drawn closer by the necklace's magic.
The werewolf part of the pregnancy could make their relationship more complex. Draco might feel a sense of protectiveness over Hermione and the baby that he didn't expect. He could start to see Hermione in a new light, as a strong and brave woman dealing with this difficult situation. For Hermione, she might see a softer side of Draco as he tries to support her through the physical and emotional changes brought on by the werewolf pregnancy. But there could also be times of tension, especially if Draco's family gets involved and tries to interfere with their relationship because of the werewolf element.