I am a Demon. (悪魔; Akuma, Devil)  A supernatural being who occasionally comes to the human world to form a Faustian contract with a human, offering a range of services in return for the future consumption of the individual's soul.
In this case, the soul of Ciel Phantomhive is mine. I shall serve him until the end of time.

I speak every language known to Humankind.

I have often been asked the following:  

"Are you a Demon? Because you are HOT as Hell."

I LOVE cats.