Their relationship would likely start off with a lot of passion and hope. However, as the years go by, they would have to deal with the pressures of the wizarding world. For example, Severus' reputation might cause some to shun Lily as well. But they would learn to rely on each other more, becoming a united front. They would also have to adapt to each other's growth. As Severus becomes more open about his feelings and Lily becomes more confident in her choices, their relationship would transform into a deep and abiding love.
At first, their relationship would likely be very strained. Given their past history of animosity, they'd probably be constantly on edge around each other. But as time passes, they might start to see each other's good qualities. Severus could come to appreciate James' courage and leadership, while James might start to understand Severus' intelligence and loyalty. Eventually, they could develop a grudging respect that turns into a real friendship and then perhaps a deeper emotional connection as they share their lives together.
At first, their relationship would be full of the excitement of newlyweds. But as time passes, they would face more practical issues. For example, they might start to have small arguments about household chores. However, through communication, they would grow closer and understand each other better.
In some fanfictions, Severus might become more open and less brooding when married to Lily. His love for her gives him the confidence to be more social. Lily, on the other hand, could become more patient as she understands Severus' past traumas better.
Their relationship would likely become more complex. Since Harry has only known Lily through memories and stories, actually meeting her in person through time travel would be a shock. Lily would see Harry as a grown man, not the baby she left behind. They might develop a more equal, friend - like relationship as they face the challenges of the time - travel situation together.
Well, initially their relationship when they get married would be quite tentative. Shinji would be unsure of how to be a good husband to Rei, and Rei would be learning about all the aspects of a marital relationship. Over time, Shinji would probably become more assertive in the relationship, and Rei would become more expressive of her feelings. They might start to have their own traditions and inside jokes. However, they could also face problems like jealousy if other characters show interest in either of them. But they would have to work through these issues to keep their relationship strong.
Often, fanfiction will explore the idea of Lily having a deeper understanding of Snape's actions and motives. This can lead to a relationship where she is more forgiving and empathetic towards him. For instance, in some stories, when Snape is bullied, Lily steps in more actively to defend him, which changes the dynamic of their relationship. In other cases, the relationship might be reimagined in a romantic way that was only hinted at in the original. There could be a scenario where they actually start a relationship during their Hogwarts years, which would completely change the course of their individual lives and how they interact with other characters like James Potter.
At first, their relationship would likely be very rocky. Severus would probably be cold and distant, still holding onto his Slytherin pride and past experiences with Gryffindors like Hermione. Hermione, on the other hand, would be confused and perhaps a bit angry about the arranged situation. But as time goes on, they might start to communicate more. Hermione's inquisitive nature could lead her to ask Severus about his past, and Severus might be reluctantly drawn into sharing some of his secrets. This sharing could be the start of a new understanding between them.
At first, their relationship might be a bit rocky. Draco, with his proud and sometimes cold nature, and Luna, who is so dreamy and unique, would need to find common ground. But as time passes, they could start to understand each other better. Draco might learn to appreciate Luna's creativity and kindness, and Luna could see the softer side of Draco that he hides from most people.
At first, they might be a bit distant as they get to know each other. But as time passes, they would become closer. Emmett's protective nature would come out more, and he would start looking out for Bella in every situation.
At first, it might be awkward. Kakashi is used to being a mentor figure, and now he's in a position of being 'adopted'. But as time passes, Naruto's positive energy starts to rub off on Kakashi. Kakashi becomes more carefree and starts to enjoy life more, like Naruto does.