The theme of transformation is likely to be present. Their physical and mental transformation into vampires would bring about many changes in their lives. It might also explore the theme of loyalty. Do they remain loyal to each other or do their new vampiric instincts drive a wedge between them? Additionally, the search for a cure could be a theme, as they might try to find a way to reverse their vampiric state.
One common theme could be the struggle between good and evil within the characters. Even as vampires, Dean and Sam might still have remnants of their former moral compasses. Another theme could be isolation, as they may be shunned by their human friends and allies due to their vampiric nature.
Power and its corrupting influence can be a theme. The new powers that come with being a vampire might tempt them to use it for their own gain rather than for good. Also, themes of identity crisis are possible. Are they still the same Dean and Sam or have they become something entirely different? This fan fiction can play with these ideas in various ways.
One possible analysis could be that it might explore the darker sides of the characters Dean and Sam in a vampire - themed scenario. Maybe it delves into how they deal with the vampiric nature, whether they resist it or succumb to it. It could also be about their relationship dynamic changing due to the vampiric influence.
For Dean, you could develop his character as a vampire by emphasizing his protective instincts, but in a more vampiric way. He might protect his territory or his 'blood sources' aggressively. His giggling could come from a place of enjoying the power he has. For Sam, his intelligence could be enhanced as a vampire. He could use his smarts to find new ways to survive. His giggling might be more of a nervous reaction to the new and often immoral things they have to do as vampires.
A recurring theme is the search for their place in the world. As hunters, they don't really fit into normal society. Fanfictions explore how they deal with this outsider status. Another theme is the power of friendship. They have friends in the hunting community, and how those relationships interact with their brotherly bond is often a topic. Also, the theme of fate and free will comes up, as they seem to be following a certain path but also trying to break free from it sometimes.
One common theme is loyalty. Dean and Sam are always loyal to each other in most of these fanfics, no matter what challenges they face. For example, in many stories, they will go to great lengths to save each other from danger.
A lot of fanfictions also explore themes of sacrifice. Dean and Sam are often put in situations where they have to sacrifice something for each other or for the greater good. It shows their selfless nature. Also, the theme of redemption can be found in some, especially when they deal with characters who have made mistakes in the past.
Well, the theme of redemption is quite common. Whether it's Dean trying to make up for past mistakes or Sam finding his way back from a dark path. Love and friendship also play a role. Sometimes it's about their relationship with other hunters or people they meet. And of course, the struggle against fate. Many fanfics have them trying to break free from a pre - determined destiny.
Well, family is a huge theme. It's not just about Sam and Dean, but also their extended family and how that impacts their lives. Sacrifice is also common. They are always willing to put themselves in harm's way for each other or for the greater good. And then there's the theme of the unknown. Fanfiction often takes them into uncharted territories in the supernatural world, exploring things that the show might not have covered yet.
One common theme could be the challenges they face. Maybe dealing with the reactions of their friends and family in the Supernatural universe. Another theme might be the change in their relationship dynamic, like becoming more protective of each other.
The theme of sacrifice is also prevalent. Since they are hunters, they are often put in situations where they have to sacrifice something for the other's well - being. This could be their own safety, a chance at a normal life, or even a relationship with someone else.
Guilt is a very common theme. Since Sam and Dean have a strong bond, when Sam hurts Dean, he often feels intense guilt which drives the plot forward.