As a secondary character, you are accepting that you may be needed in short bursts. With such a large cast of secondary characters, there may be bursts where you are important to the releases and needed frequently, as well as bursts where you are not needed for an extended period of time.

Earth is a feminine echoing voice that communes directly with Diting, offering advice whenever the chief executor of hell requires it. Earth does not appear in every Diting chapter, but I am unsure the exact amount.