Their relationship can develop through shared experiences. For example, if they are trapped in a dangerous dungeon together, they have to rely on each other to escape. This builds trust between them.
A situation where Mario saves Goombella from a near - death experience can also be a turning point. After that, Goombella becomes more determined to prove herself useful to Mario. She starts to train hard and shows her loyalty, which in turn makes Mario respect and care for her more.
Maybe Mario saves Pauline from a series of dangerous situations, and as a result, Pauline begins to see Mario in a new light. She starts to do things to show her gratitude, like making him special power - up treats. This back - and - forth interaction can develop their relationship.
For Mario, you can develop his character by showing his internal struggle between his duty to the Mushroom Kingdom and his growing feelings for Bowsette. He could be hesitant at first due to her previous villainous actions. For Bowsette, explore her softer side. Maybe she has insecurities about being accepted by Mario and the others in the Mushroom Kingdom. This could be shown through her interactions with Mario and how she reacts when faced with rejection or suspicion.
Another plot could be that Mario gets injured and Goombella has to take on a more leading role in their journey. She uses her knowledge and unique abilities as a Goomba - like being able to sense danger from afar - to protect Mario and continue their mission to retrieve a powerful artifact that was stolen.
Their relationship can be developed through shared experiences. For example, they could go through a tough battle together. During the battle, Kazuma could protect Bishamon from a near - fatal blow, making her see him in a new light. And Kazuma could also admire Bishamon's strength even more.
Their relationship can be developed through shared experiences. For example, if they go through a dangerous dungeon together, Bell can protect Hestia and she can in turn use her divine powers to support him. This mutual reliance will strengthen their bond.
Their relationship can be developed through shared dreams. In the fanfiction, they could start having the same strange dreams that show them memories from their past lives together. This would make them start to question their connection and lead to them spending more time together to figure it out.
Their relationship could develop through mutual discovery. For example, Peridot could show Yellow Diamond the unique aspects of Earth that she has come to appreciate. Yellow Diamond, in turn, could share some of her knowledge of the Gem Homeworld with Peridot, creating a bond based on the exchange of ideas.
Their relationship could be developed realistically by having them work towards a common goal. For example, they might be trying to stop a new villain from taking over the world. As they plan and execute their strategies, they see the best and worst in each other. Gohan might see Android 18's determination even in the face of great danger, and Android 18 might see Gohan's selflessness. These experiences can bring them closer and form a relationship based on trust and admiration.
Their relationship can be developed by showing small, everyday interactions. For example, sharing a meal and chatting about their day in the clan. This would build a sense of closeness and familiarity.
Their relationship can be developed through shared experiences. For example, if they face a common enemy together. This would force them to rely on each other, communicate, and understand each other's strengths and weaknesses. In the heat of battle, they might develop a mutual respect that blossoms into a deeper friendship.