Consort.

A Consort is an invisible creature designated to follow a specific human being, to write down his every single movement. Tom is a Consort. He is chosen to follow Derek Blackthorn, a dark magician who had embraced the fact that he was going to rot in hell.
And so one day, Derek decides to get rid of his Consort. He decides to get rid of Tom, which mysteriously causes Tom to end up as Terry Hastings Consort.
Terry Hastings is a black cat. She has absolutely no luck in her life. Sometimes, she wondered if someone had laid a dark spell of miserableness over her when she was a child. She hates her life and doubts if it will ever change to the best. She just hoped that there is an actual thing called an afterlife, where she could at least be happier than she is in the present day.
Little did the Consort and the human know that when they collide, their lives were going to change one-hundred and eighty degrees.
But will it change to the better, or to the worse?