One popular book could be 'Lover Awakened'. It has a great story with complex characters. The intense relationships between the characters really draw readers in.
Another notable one is 'Lover Reborn'. This book continues to build on the world that has been established in the series. It has a lot of action, as the Brotherhood battles their foes, and at the same time, there are tender and passionate moments between the characters that make it a great read.
Wrath is one of the main characters. He is a strong and powerful leader in the Brotherhood.
Wrath is a very popular character. He's the king of the vampires and has a strong and complex personality. Another popular one is Butch. He's a human who gets involved with the Brotherhood in a very unique way.
The complex characters are a great aspect. Each brother in the Black Dagger Brotherhood has a unique backstory and personality. Their relationships, both within the brotherhood and with the outside world, add depth to the stories.
The theme of Wrath's leadership within the Brotherhood in relation to his relationship with Beth is also common. Writers might show how his role as a leader affects his time with Beth and vice versa. For example, how he has to balance protecting the Brotherhood and loving Beth. It's a complex dynamic that makes for interesting fanfiction.
Fanfictions that focus on the training regimes of the Brotherhood can also be really engaging. They can detail the intense physical and mental training that the warriors go through. This not only gives readers a better understanding of how the characters become so strong and skilled but also adds an element of action and adventure to the story.
One of the main themes is loyalty. The Brotherhood members are extremely loyal to each other in their fight against the Lessening Society. Another theme is love and sacrifice. We often see characters sacrificing their own well - being for the sake of their loved ones or the greater good within the vampire society depicted in the novels.
Wrath is often a very popular character in fanfic. As the king, he has a lot of power and responsibility, which makes for interesting storylines. His relationship with Beth is also a big draw, and many fanfics explore different aspects of their relationship, like how they deal with ruling together.
Rhage is also important. He has a beast within him, which makes his character both dangerous and endearing. His relationship with Mary is a significant part of the story.
The novels usually have a richly developed supernatural world, complex characters with deep backstories, and intense romantic plots.
One interesting story could be about the intense brotherhood bonds among the characters. Maybe a story where they face a great external threat together and how their loyalty to each other is tested and prevails.