Often, they start with some form of unexpected encounter. For example, they might meet during a Quidditch match where Daphne is injured and Harry helps her. This initial interaction plants the seed for their relationship. Then, when they sleep together, it could be a sign of the deepening trust and closeness between them. It might be in a situation like they are both hiding from some dark magic forces and have to stay close in a small, secret place for the night.
In the fanfiction, their relationship could develop in a rather unexpected way. Since they live together, they are constantly in each other's presence. Harry might start to teach Daphne some of his Quidditch moves in the backyard, and Daphne could introduce Harry to some of the more sophisticated Slytherin social etiquette. As they engage in these activities together, they start to respect and admire each other more. Eventually, this could lead to a romantic relationship or a very deep friendship depending on how the author wants to take the story.
In this fanfic, Harry would likely grow in his social skills. Since Daphne has different social circles, he'd be introduced to new people and ways of interacting. He might become more diplomatic, learning from Daphne how to handle different personalities gracefully. Daphne would develop a stronger sense of loyalty. As she gets to know Harry better, she'd see his unwavering loyalty to his friends and causes, and this would inspire her. She might also become more adventurous, as Harry often gets into exciting (and sometimes dangerous) situations, and she'd be drawn into them, expanding her own boundaries.
In some fanfictions, their relationship develops through shared secrets. Daphne might share some Slytherin secrets with Harry, and in return, Harry tells her about his experiences with Voldemort. This sharing of personal and important information brings them closer together. They start to rely on each other more and more, and eventually, their relationship can range from a deep friendship to a romantic one, depending on the direction of the fanfiction.
The relationship could also develop through cultural exchange. Daphne, being from a pure - blood Slytherin family, has different values and traditions compared to Harry. As they get to know each other, they introduce their respective cultures to one another. This leads to a deeper understanding and a more profound emotional connection between them.
One popular story could be where they have a magical adventure together before falling asleep side by side. In this kind of fanfiction, they might be in a situation where they are exploring an ancient magical ruin and get tired, then find a safe place to rest and end up sleeping close to each other as they feel a new - found bond during the adventure.
Well, usually the fanfictions develop their relationship through a series of events. For example, they might be forced to work together on a difficult task at Hogwarts. During this process, they begin to respect each other's skills and knowledge. As time goes on, they start to have feelings that are more than just respect. Some fanfictions also explore how their past traumas can bring them closer. Snape's past with Lily and Harry's with his parents' death can be a starting point for them to connect on a deeper emotional level. And often, the relationship develops in a way that challenges the norms of the wizarding world.
Often, these fanfictions develop their relationship through shared experiences during the Triwizard Tournament. For example, when Harry is facing the tasks, Cho could be shown as a source of moral support. They might also develop their relationship through conversations at the Yule Ball. In some fanfictions, they might bond over their love for Quidditch.
Often, they start with animosity. Rose, being Hermione's daughter, might be suspicious of Scorpius due to his family's past. But as they interact more, like in study groups or on school projects, they begin to see each other's true selves.
It could start with a simple conversation in the library. Daphne might be reading a book on dark magic defenses and Harry asks her about it. From there, they start to exchange knowledge and stories. As they learn more about each other's pasts and dreams, their relationship blossoms into a deep friendship or even something more romantic.
It could develop into a strong friendship. Since they meet as babies, they grow up with a sense of familiarity. They might trust each other more than others and always be there for one another.