Welcome to this random idea I came up with!

Josh didn't live a very interesting life. He worked a regular job at a regular office with regular friends. He was a stereotypical 'normal person'.
But what happens when his normal life becomes much more extraordinary?
After being invited to a party by one of his more rowdy friends, he finds himself in a dangerous situation. He fights back in self defense and accidentally kills the man. He tries to continue his life as it was, but a waking up to the ghost of his attacker the next morning throws his plans out the window. Now, he needs to learn how to live with a vengeful ghost and a secret criminal record.