In a zombie-apocalypse MMORPG, an Undead from Dark Souls somehow ends up among the NPCs.
"What are you, an Undead, doing messing around in a zombie game?"
"Zombies aren't so inconvenient.
They walk slowly and don't fear death. That makes them zombies," he said, pointing at the Hollows.
"Then why don't you turn into a Hollow?!"
"No, you still don't get it. An Undead wearing Havel's Set and carrying too much weight is a zombie, too."
PS: The setting of this novel is a zombie-apocalypse MMORPG as its main world, with lots of anime and game instances. The protagonist is an NPC who can become an Undead.
First instance: Dark Souls I
Second instance: Dying Light 2
PS2: No cultivation! The protagonist gets stronger by killing monsters and leveling up.