sebastian x undertaker fanfiction: What are some interesting plot ideas?

One idea could be that they are forced to work together on a mission in the human world. They initially clash due to their different methods but gradually come to respect each other. Another could be a time - travel plot where they end up in a different era and have to rely on each other to get back. Or perhaps they meet in a magical realm that is neither their own and must team up to escape.

One idea could be that the reader is a new undertaker's apprentice. They start off being clumsy and Undertaker finds it both amusing and endearing. As time passes, a deep bond forms between them, and they face various supernatural challenges together in the world of Black Butler.

One great 'Undertaker x Sebastian' fanfiction is 'The Unlikely Alliance'. It delves into a scenario where they have to work together to solve a mystery in the underworld. The story is filled with interesting character interactions and a touch of humor.

One idea could be Sebastian protecting Ciel from other alphas who see Ciel as a desirable omega. Another could be Ciel struggling with his omega instincts while trying to maintain his role as the head of the Phantomhive family. Maybe Sebastian and Ciel could go on a journey together where they have to rely on each other and their bond deepens as a result.

One plot idea could be that the OC is a new servant in the Phantomhive household. Sebastian initially views her as a nuisance but as they interact more, a strange attraction develops. For example, during a ball at the manor, the OC accidentally spills wine on a noble guest. Sebastian steps in to save the situation and in the process, he realizes her charm and quick - wittedness.

One idea could be that fem Ciel has to attend a grand ball and Sebastian helps her get ready in a very intimate way, like choosing the perfect dress and doing her hair, while they share some flirty banter. Another could be that fem Ciel gets into trouble with a rival noble and Sebastian uses his demonic powers in a very creative way to protect her, all while their relationship deepens. And perhaps a plot where fem Ciel discovers a secret about Sebastian's past that makes her see him in a new light and changes the dynamic of their relationship.

A more complex plot could be that they are not sure who the father really is. This creates a lot of drama and tension. They could go through a process of trying to find out the truth, all while dealing with the fact that they are about to become parents. Their relationship might be on the rocks because of the uncertainty, but in the end, they realize that no matter what, they want to raise the baby together.

One idea could be that the Undertaker is secretly protecting the main character of Black Butler out of love. He uses his unique skills and knowledge to keep them safe from various threats in the dark underworld of the story.

One plot idea could be that Vincent, before his death, made a secret pact with Undertaker that is only revealed years later. For example, it could be related to the future of the Phantomhive family and the underworld they are involved in. Another could be a story where Undertaker has memories of Vincent that he has never shared, and these memories start to surface when he meets Ciel, causing him to act in unexpected ways towards Ciel. Maybe there's a plot where Vincent's spirit is trapped in a limbo-like state, and only Undertaker can free him, but it comes at a great cost to the balance of the afterlife world in the Black Butler universe.

One interesting plot could be Undertaker's past being explored in more detail. Maybe he had a relationship with one of the other main characters' ancestors that comes to light and affects the present story. For example, if he had a connection with Ciel's family long ago.