Klient Koid is a "Ghost for Hire"—a spirit who hasn't moved on because he acts as a consultant for the living who want to communicate with the other side.
It’s possible the name is slightly different from how you remember it. You might be thinking of: Klient Koid Ghost
A famous ghost in Indonesian/Malay mythology often depicted as a woman with long hair (sometimes confused with "Klient" phonetically). Klient Koid is a "Ghost for Hire"—a spirit
If you were looking for a about a character named Klient Koid who is a ghost, here is a short conceptual summary: was it in a video
For example, was it in a video, a specific book, or a local story from a particular country? Knowing the context will help me get you the exact information you need.