Themes like power imbalance and how it affects their relationship are quite common. Since Dream is often associated with positive power and Nightmare with negative, their yaoi relationship in fanfictions might explore how they deal with this difference. Also, the theme of self - discovery within the relationship is popular. As they get closer, they might discover new things about themselves and their own powers.
One popular theme could be redemption. Nightmare, being the more 'evil' of the two in the original concept, might find redemption through his relationship with Dream. Another theme could be forbidden love, as they are on opposite sides of the spectrum in 'dreamtale'.
I'm not really into yaoi fanfictions, but generally, in 'dreamtale', Nightmare and Dream are two important characters. In yaoi fanfictions about them, it often explores their complex relationship in a romantic or emotional way. Writers might focus on their opposing natures, like Nightmare being more on the dark side and Dream on the light side, and how they interact and perhaps develop feelings for each other in this fictional context.
One popular theme is the reconciliation between Nightmare and Dream. It often involves them overcoming their differences and past conflicts.
One common theme is the exploration of duality. Since Dream and Nightmare are opposites, many fanfictions explore how they are two sides of the same coin. For example, how Nightmare might have some good in him despite his dark nature, and vice versa for Dream.
One common theme is the exploration of the dark side. Since they are nightmare - based characters, a lot of fictions focus on their sinister nature.
Isolation is also a common theme. Light is isolated in his grand plan to create a new world, and Ryuk is isolated in his existence as a Shinigami. Their relationship in fanfiction can be a way to break that isolation for both of them. It can be a connection that neither expected but that becomes essential to their characters' development.
One common theme is the exploration of their relationship dynamics. Since yaoi focuses on male - male relationships, it might show how they gradually develop feelings for each other, from initial acquaintance to deep emotional connection.
One common theme could be the exploration of their contrasting personalities. Squidward's grumpiness and Spongebob's extreme cheerfulness can create an interesting dynamic in the fanfiction. For example, a story might revolve around Squidward slowly warming up to Spongebob's affections in a non - traditional way. Another theme could be the setting of their underwater world being used in unique ways to bring them closer, like an adventure that forces them to rely on each other.
Another theme is the exploration of their complex relationship. They have a sort of rivalry but also a deep connection. Fanfictions might focus on how they come to terms with their feelings for each other, whether it's a slow - burn kind of realization or a sudden epiphany. It often delves into their psychological states as they navigate this new aspect of their relationship. And this can be really interesting as it gives a different perspective on their characters than what we see in the original series.
One popular theme is the idea of protection. Levi, being the more skilled and powerful one, often takes on the role of protecting Eren. This can be both physically, in battles against Titans, and emotionally, as Eren grapples with the complex world he's in.
One popular theme could be the exploration of their complex relationship. Their unspoken bond and how they support each other in the face of various challenges. Another might be the growth of their relationship over time, from initial hesitance to a deeper connection.