Demon Slayer: Upper Rank Zero Is Surprisingly Useless

What happens when the most powerful demon rank belongs to the weakest member? Meet Upper Rank Zero—a fragile, memory-less demon raised by Muzan himself, whose childlike innocence makes him the beloved darling of the demon hierarchy. Younger than even Rui, this non-combat protagonist navigates a brutal world with a worldview shaped entirely by demonic influence. No system, no predetermined romance, and absolutely no memories of his human past. A unique take on the Demon Slayer universe where power doesn't equal strength, and the most dangerous position goes to the most vulnerable demon.