One common theme is the exploration of their deep emotional connection. Since they have a strong bond in the show, fanfictions often delve into how that bond could turn into a romantic relationship. For example, stories might focus on how they deal with their feelings in a world where hunters usually don't have time for love.
The theme of acceptance is also prevalent. Dean, coming from a more traditional background, might struggle with accepting his feelings for Castiel, who is an angel. Fanfictions often explore how he overcomes his internalized homophobia or the expectations of his hunting family. Castiel, on the other hand, might have to deal with the angelic hierarchy and their views on relationships. These stories show how they grow and accept their love for each other in the face of these challenges.
Another theme is the idea of sacrifice. In the Supernatural universe, both Dean and Castiel have sacrificed a lot. Fanfictions might show how their love for each other makes them willing to sacrifice even more. It could be sacrificing their own well - being or even their lives to protect the other. Also, there are often themes related to the supernatural world they inhabit. How their relationship is affected by the angels, demons, and other creatures they encounter. Maybe they have to fight against supernatural forces that are against their relationship.
One common theme is loyalty. In many of these fanfictions, Dean and Castiel show unwavering loyalty to each other, whether it's facing the forces of evil in the Supernatural universe or dealing with personal issues. Another theme is sacrifice. They are often willing to sacrifice themselves for the other's well - being.
Often, the theme of sacrifice is present. Maybe one of them has to make a big sacrifice for the other, and the kiss is a moment of intense emotion before or after that. It could also be about them breaking free from some kind of supernatural constraint that has been holding them back from being together, and the kiss is a symbol of their newfound freedom.
Romantic relationships between them are also a popular theme. Writers might explore how a relationship between an angel (Castiel) and a hunter (Dean) would work, dealing with the differences in their natures, their loyalty to their respective worlds, and how they overcome obstacles to be together.
One common theme is the vulnerability of the characters. When either Castiel or Dean is sick, it shows a side of them that is not often seen in the show. They usually rely on each other for support, which is another theme. For example, Dean might take care of Castiel in a more gentle way than he normally shows, and vice versa.
One common theme is the struggle with identity. Dean, being a tough hunter in the show, often has to come to terms with his new - found feelings for another male in the fanfiction. It's about him finding himself in a different light.
One common theme is the idea of unconditional support. Castiel is often depicted as being there for Dean no matter what, through his darkest moments. For instance, when Dean is haunted by his past actions or when he's feeling extremely guilty.
One common theme is friendship. Their bond, whether it's a platonic friendship or something more, is often explored. Writers like to show how they support each other through tough times.
There are fanfictions with the theme of alternate universes. In these stories, Dean and Castiel experience different versions of their relationship. For example, in one universe they might be rulers of a supernatural kingdom, and in another they could be ordinary humans. These themes add a lot of variety and intrigue to the fanfictions.
A common theme is friendship. Often, the stories focus on how the reader becomes friends with Dean and Castiel. Another theme is adventure. Since they are hunters in the Supernatural world, they go on many adventures together with the reader. For instance, they might go on a quest to find a powerful artifact.
One common theme is the exploration of forbidden love. Since Castiel is an angel and Dean is a human, their relationship often goes against the norms of both their worlds. Another theme is sacrifice. They are often willing to sacrifice a great deal for each other.