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
Yi Bing hasn't thought of the Life Record before, since he is disinterested in everything. Even the position of being the director of the Afterlife Department doesn't interest him. It's like he has no needs, nor even a want. He even felt his existence is disinteresting. His gray life only started to have a color when he was given a soul assignment.
But, Huo Ling's appearance erased all the remaining grayness in his life. This is how significant and important Huo Ling is to him. He started to have an interest, and later, started to have a need – Huo Ling. This feeling intensified when he learned that Huo Ling is connected to his past life. Thus, he wanted to know how, and what is his exact relationship to Huo Ling.
Yi Bing opened the Life Record and saw the first world Lei Shan was in is the Zombie Apocalypse World.