50,000 years ago, Hell was destroyed because of too much Foul from the resentment of the souls that later turned to Soul Eaters and devoured everything in their wake, leaving nothing of Hell. The gods above in Heaven, in order to take care of the newly-died souls, created the Afterlife Department comprised of grim reapers. Huo Ling was delivering food that day when he met Yi Bing and the guy gave him a warning. When he arrived to the customer's unit, he was killed. Huo Ling: you set up a death flag for me! Yi Bing: I'm a grim reaper. I'm the flag myself. Let me help you solve the mystery of your death. Huo Ling: your sister! Alternative title: The Different Ways I Died at 23 Update: daily
Xie Chen nodded in agreement. "Yes. This is fair." He said as he flipped the pages of the documents that he is holding. If Yi Bing doesn't even know to verify any information that was presented to him, then Xie Chen would personally kick him in the head for being so muddle-headed. Fortunately, Yi Bing is sober, and this is why Yi Bing is one of the people… ehem, grim reaper that he trusts.
Yi Bing is a competent grim reaper, no doubt about this. Thus, Xie Chen could trust Yi Bing with the Afterlife Department's cooperation with Gu Lin to work in the mortal realm. That is, look after the mortal realm from the scheming of the secret organization Re. And one of their scheming is the Soul Eaters. As for the other, it is to destroy the other worlds using the portal that they created that could lead them to the other worlds.