Ssiyh

You can create the story entirely yourself; I won't limit you. As the fandom grows, I'll continue to add characters, flora, and so on.

Functions of this world:
Ssiyh is a universe into which everyone enters from the real world. Souls arriving here initially remain in a void of storage, and every month, an unknown long tube comes to them, sucking one of them in. Afterward, when the soul slips through the tube, it is given a choice between three specific black bodies. When it chooses a body, the "god of this world" throws it down, and it lands abruptly on the ground in the body it chose. And so begins their first life. Two to six weeks after its appearance, it can randomly change form, losing its black color and becoming the final version of itself in this world. They then live for eternity, until they begin to fall into depression or dwell on their thoughts too often, at which point they are visited by what they call "death." Everyone who has interacted with "death" says it is very comfortable and friendly. Despite these stories, everyone died a month later from her own pistol, accepting her choice between living and dying. No one knows the reason for this behavior, but no one can learn it from the dead. Also, the bodies of the dead must be taken outside the city walls immediately, as within a few days they will deform and reanimate, this time as monsters. Monsters can easily cause harm even accidentally, and no one understands them, so they are thrown out of the city. Outside the city to the northwest, there is a rotten black forest, where they are thrown.

The description also contains categories for dividing all creatures and the city.

Some bookmarks that will make searching easier:
✋ — resident
🐺 — animal
💀 — dead
🌸 — plant