Sebastian is always popular. In Black Butler Stainless fanfiction, he could be portrayed as having a special connection to stainless - steel objects, perhaps using them in his demonic tasks in a unique way.
Ciel is also a very popular character. He might be involved in a plot where he has to use stainless - steel weapons or tools to fight against new enemies in the fanfiction world.
Grell is another character that often appears in fanfiction. In the context of Black Butler Stainless, Grell could be obsessed with the shiny appearance of stainless - steel and get into all sorts of comical situations because of it.
There might be a fanfiction where Ciel discovers a secret society within the 'Black Butler' universe that is centered around the creation and use of stainless items for magical purposes. This could involve a lot of mystery and intrigue as Ciel tries to figure out their motives.
Ciel is also very popular. Picture a scenario where Ciel finds a cat and decides to keep it. The dynamic between him, a young noble with a dark past, and the cat can create some really heart - warming or suspenseful moments. The cat could either be a source of comfort for Ciel or bring new challenges to his already complex life.
Ciel is definitely one of the most popular. His complex personality and his tragic backstory make him a great focus for fanfiction. Writers can explore his inner thoughts and feelings more deeply. Sebastian is also very popular. His demonic nature and his loyalty (in a rather twisted way) to Ciel are fascinating aspects to write about. Grell is another popular character. His flamboyant and somewhat deranged personality offers a lot of room for creativity in fanfiction.
William T. Spears is also quite popular. His strict and no - nonsense attitude provides a great contrast to other more chaotic characters, and fanfiction often plays with his interactions with other reapers or the main Black Butler characters.
Grell is quite popular as well. His over - the - top personality and his unorthodox views make for some really entertaining reaction scenarios. He can go from being overly dramatic to having some surprisingly deep insights in fanfiction.
Ciel Phantomhive is often paired with the twins in fanfiction. Since he is a central character in the Black Butler series, writers like to explore different dynamics between him and the twins, such as a power struggle or a forced alliance.
In addition to the main characters, characters like Finny, the gardener with his superhuman strength, can be interesting to feature. Fanfiction can explore his backstory more deeply, like how he got his powers and how he copes with being different. Bardroy, the chef, is also a character that can add a lot to a story. His military past and his rather unique cooking skills (or lack thereof) can be a source of great stories in fanfiction.
Sebastian is often very popular. His demonic charm and loyalty to Ciel, despite his ulterior motives, make him a fascinating character to write about. Fanfiction writers can explore his internal struggles between his demonic nature and his growing attachment to Ciel.
Hermione Granger often appears in crossovers. Her intelligence and magical abilities from the Harry Potter series can be paired well with the more gothic and dangerous world of Black Butler. For instance, she might use her knowledge to outwit the demons or help Ciel solve a difficult case that has a magical element to it.
Typically, the main characters would be the ancestors themselves. They could be the ones with special powers or unique personalities that drive the story forward.