One tickle story could be when Sebastian might playfully tickle Ciel as a way to amuse him during a less tense moment. Maybe when Ciel is feeling a bit down and Sebastian uses tickling to cheer him up, making Ciel giggle despite his usually serious demeanor.
As far as I know, there are no official tickle - related events in a very direct sense. However, the characters do have moments of light - heartedness and playfulness that could potentially involve tickling in fan interpretations.
The story of how Ciel made a contract with Sebastian is quite memorable. Ciel, in his quest for revenge after the death of his parents, sold his soul to Sebastian in exchange for help in achieving his vengeance. It's a dark and compelling start to the series.
Another important character is Grell Sutcliff. He's a reaper. Grell has a flamboyant personality and his own goals and desires which often intersect with the affairs of Ciel and Sebastian. His presence adds a lot of chaos and mystery to the 'Black Butler stories'.
Definitely not. The Black Butler series has a set of established themes such as the supernatural elements, the Victorian - era setting, and the complex character relationships. The idea of a 'leashed slave story' is completely foreign to the official canon and is likely a disturbing creation outside of the proper series. It would go against the overall tone and moral framework of the official work.
One interesting story is about how Sebastian, the demon butler, always manages to fulfill Ciel's requests in the most extraordinary ways. For example, when Ciel has to attend a dangerous social event, Sebastian uses his demonic powers subtly to protect Ciel while still maintaining the appearance of normalcy.
There is indeed a 'Black Butler' visual novel. It features the same dark and alluring art style as the anime and manga. The visual novel might include different storylines, some of which could be exclusive to this format, providing a new perspective on the 'Black Butler' world. It often has a strong focus on character development and the complex relationships within the story, which is great for fans who want to explore more about the characters.