You can develop their relationship further by adding more challenges. For instance, introduce a character who is jealous of their relationship and tries to drive them apart. This could test their love and loyalty to each other. They would then have to fight for their relationship, which would strengthen their bond in the end.
Show their relationship in different settings. Instead of just the castle, put them in a situation where they are traveling to a neighboring kingdom. On this journey, they have to rely on each other in new ways. They might face difficult situations like getting lost in a forest or dealing with unfriendly locals. Through these experiences, they discover new sides of each other. For example, Adam might find out that Belle is really good at bargaining when they need supplies, and Belle might see Adam's diplomatic skills when they meet with the leaders of the neighboring kingdom.
In fanfiction, Belle's character could be further developed by having her struggle with her own insecurities. Maybe she feels that she's not enough to fully break the curse. Adam, on the other hand, could be developed by showing his internal conflict of wanting to be fully human again but also being afraid of losing the part of him that Belle fell in love with as the beast. Their relationship could grow as they help each other through these internal battles.
A great way to develop their relationship further is to show them building a life together. They could start a project like building a lighthouse that has a special connection to both the land and the sea. It would be a symbol of their love and unity, and during the process of building it, they would face challenges, make compromises, and grow even more in love.
They could start sharing more personal stories. For example, Ciel could open up about his past traumas to Soma, and Soma could share his dreams for his homeland. This would create a deeper emotional connection between them.
One way is by having them face family opposition. Maybe their families have different political views or old feuds. Standing up for their relationship against all odds can strengthen their bond. They could also communicate through letters at first. This old - fashioned way of communication can be very romantic. As they exchange their thoughts and feelings in writing, they start to develop feelings for each other before they even meet in person.
They could be given a task that requires them to rely on each other completely. Let's say they have to find a lost heirloom in a far - off land. Along the way, they share stories from their childhoods that they haven't told before. Rapunzel tells Flynn about her lonely days in the tower in more detail, and Flynn opens up about his early days as a thief. This deepens their bond.
Their relationship can be developed by showing them learning about each other's cultures more deeply. For example, Ariel can teach Eric more about the different species in the ocean, their languages, and their traditions. This would bring them closer as they understand each other's worlds better.
As time passes, they start to understand each other more. Adam might show Belle parts of the castle she hasn't seen before, and in the process, they share stories. Belle learns about Adam's past and the curse that befell him, which makes her feel sympathetic towards him. This deepens their bond.
Their relationship would likely become even deeper. Adam would be more protective of Belle, constantly worried about her and the baby's well - being. Belle, on the other hand, might become more reliant on Adam's support during her pregnancy.
They could have more deep conversations about their future as a family. For example, discussing how they want to raise their children, what kind of values they want to instill. Also, showing them supporting each other in small daily things, like Lucy helping Natsu with his reading skills and Natsu helping Lucy when she has a tough day at the guild. This would strengthen their bond on a more personal level.
The relationship can be developed by having them face difficult challenges together. For example, in a tough Pokémon battle where they are outnumbered. They have to rely on each other's skills and instincts to win.