HuilongShenghou

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

Afterlife Department

"That's right." Gu Shi nodded. "But, the souls of this world are reincarnating internally, so, external reincarnation is out of the options." He said. "As for them being dead…" he looked at Yi Bing.

"It isn't possible, either." Yi Bing said.

"En. Because only their presence disappeared and not their existence." Huo Ling spoke. "It means that the souls are still alive." He said.

Gu Shi gave Huo Ling a thumb's up.

"By their presence disappearing, it might be that their soul is too weak to be detected." Huo Ling spoke, then shook his head. "No. If their soul is too weak to be detected, then how can we say that they disappeared?" he asked. "We can say they disappeared because we have detected them first, but then something happened that made their soul became weak… weak enough for us to lose them to be detected." He explained.

Deduction