One interesting Black Butler Beast fanfiction could be one that explores her backstory in more detail. Maybe it delves into how she became the way she is, her past experiences in the circus and how it shaped her personality. It could show her relationship with the other circus members in a new light, adding depth to her character that wasn't fully explored in the original work.
There could be a fanfiction where Paula takes on a more active role in solving the mysteries that Ciel faces. Maybe she teams up with Sebastian secretly and uses her own unique skills, like her knowledge of the local area and its people, to help gather information. This would change the dynamics of the usual Black Butler story.
One interesting 'Black Butler Sebastian' fanfiction could be those that explore his past before becoming a demon. For example, there might be stories about his life as a human and what led him to make the pact that transformed him. Another type could be fanfictions that focus on his relationship with Ciel in alternate universes, like a modern - day setting where they have different dynamics. There are also fanfictions that give Sebastian more human - like emotions and struggles, which can be really engaging to read as it adds a new layer to his character.
One interesting 'Black Butler Pluto' fanfiction could be one where Pluto has a more complex backstory. For example, it might explore his life before he became a demon hound. Maybe he was once a normal dog with a kind owner, but some tragic event led to his transformation. Another could be a fanfiction where Pluto has to choose between his loyalty to Sebastian and his own new - found sense of self.
There are fanfictions that might create alternate endings for the 'Book of the Atlantic' story. Maybe in one, Sebastian and Ciel's relationship takes a different turn. Instead of the usual master - servant dynamic, they form a more equal partnership in facing the threats in the Atlantic adventure.
There might be a fanfiction where a cat in heat is used as a symbol or a plot device. For example, it could be a part of a mystery that Ciel is trying to solve. The cat's behavior due to being in heat could lead to some unexpected clues or events in the story.
One idea could be that Sebastian from Black Butler gets transported into the world of Beauty and the Beast. He could use his skills to help the Beast court Belle in a more sophisticated way. For example, he might plan elaborate balls or dinners. Another plot could be that Ciel is cursed like the Beast and Belle is a character who is brought in to try and break the curse, but she has some secrets of her own related to the Black Butler universe. Maybe she has a connection to the underworld that Ciel is also involved in.
Another place to look is Fanfiction.net. There are many Black Butler Beast fanfictions there as well. However, the quality can vary more compared to AO3. But if you're willing to dig through, you might find some hidden gems. Look for ones with high reviews and ratings to ensure a better reading experience.
One sad Black Butler fanfiction could be about Ciel's inner turmoil. In many stories, the author delves deep into his past traumas and how they continue to haunt him. It shows his struggle to maintain his composure while facing new threats and the emotional toll it takes on him.
There's 'The Earl's Unforeseen Blessing' in the realm of 'Black Butler' mpreg fanfictions. This type of fanfiction usually plays with the existing relationships in the 'Black Butler' world. For example, it could show how Sebastian, the demon butler, deals with his master in such a situation. It might also include elements of mystery as to how this mpreg situation occurred in the first place.
There's a fanfiction called 'Finnian's Secret Admirer'. In this story, Finnian unknowingly has a secret admirer within the manor. It's a cute and light - hearted take on his character, exploring his relationships with the other servants in a new way. The interactions between Finnian and the other characters are really well - written and add a new dimension to his character.