To write a great fanfiction about Ciel's little sister, start with a strong backstory. Explain how she ended up in the Phantomhive family. Was she adopted? Or is there a more mysterious origin? Build on her relationships not just with Ciel, but also with the servants. For instance, a budding friendship with Finny could show her kind - hearted side. When it comes to the plot, make it engaging. Maybe she discovers a conspiracy that threatens the family and has to use her wits to solve it. Don't forget to give her growth throughout the story. She should change and develop as she faces different challenges. And use vivid descriptions to bring her world to life, whether it's the grandeur of the Phantomhive manor or the seedy underbelly of London.
One common theme is the sister's relationship with Ciel. In many fanfictions, she might be a source of comfort for Ciel in the dark world he inhabits. For example, she could be the only person he allows himself to be vulnerable around. Another theme could be her own adventures within the Black Butler universe. Maybe she has to face off against the same villains as Ciel but in her own unique way. Also, her backstory often plays a role. Writers might explore how she came to be in the Phantomhive household and what her life was like before. This can add depth to her character and her interactions with other characters in the story.
Well, first, you could give her a distinct personality. For example, if Ciel is more reserved and calculating, she could be outgoing and impulsive. This would create an interesting dynamic when they interact. You can also develop her backstory. Say she had a special relationship with a particular character in their childhood that influenced her actions in the present.
A fanfiction could focus on how Ciel's eye affects his relationships. For instance, some might be afraid of it, while others, like Sebastian, might be intrigued. It could explore how his eye makes him both a target and a symbol of power among the various factions in the 'Black Butler' universe.
First, you need to set the scene. Describe how Ciel starts to feel unwell. Maybe it begins with a slight shiver or a tickle in his nose. Then, when it comes to the sneezes, be creative. You could write something like 'Ciel's small frame was wracked with a sudden sneeze, his hand flying to his face.' Also, consider how the other characters will react. Sebastian might be both concerned and a bit amused at his master's vulnerability.
One idea could be that Ciel's sister was secretly alive all along and has been in hiding, training to avenge the family. She could emerge with unique powers and a strong will, partnering with Sebastian in unexpected ways to take on the enemies that Ciel has faced.
One plot idea could be that Ciel's twin sister was hidden away by their enemies at a young age. She could return years later, having been trained in secret combat and magic skills. She then helps Ciel in his fight against the demons and the underworld, using her unique abilities that Ciel doesn't possess.
A fanfiction could explore a different timeline where Ranmao becomes Ciel's bodyguard instead of Sebastian. This would lead to a whole new dynamic as Ranmao has her own unique skills and personality compared to Sebastian. She might be more impulsive in protecting Ciel, which could lead to some interesting situations.
The way Sebastian interacts with other characters in relation to Ciel can also show his hatred. He could be overly critical of Ciel in front of others or even try to undermine Ciel's authority subtly.
Highlight the contrast between them. Female Ciel is human with human emotions and motives, while Sebastian is a demon with his own set of rules. This contrast can create great tension and chemistry. For example, when faced with a moral dilemma, Female Ciel's reaction might be very different from Sebastian's. Their exchanges during such moments can be used to deepen their relationship on paper.
One possible fanfiction could be where Ciel is in the middle of a tense negotiation with an important noble. Suddenly, his asthma is triggered by the thick cigar smoke in the room. Sebastian, his butler, quickly comes to his aid, using his demon powers subtly to ease Ciel's breathing while still maintaining the guise of a normal butler. Ciel tries to hide his weakness but the noble notices and tries to use it to his advantage, creating a tense situation full of political intrigue and personal struggle for Ciel.