Demiurge

Demiurge is one of the most prominent characters in the anime Overlord. He serves as the Floor Guardian of the 7th Floor of the Great Tomb of Nazarick, the Commander of its NPC defenses, and effectively the second-in-command among the Floor Guardians.

He is an Arch-Devil (a high-ranking demon) created by the former player Ulbert Alain Odle. Demiurge is extremely intelligent, highly strategic, and ruthlessly evil — often considered one of the most sadistic and purely malevolent beings in Nazarick (with a karma value of -500, meaning "pure evil").

Appearance: He usually appears as a tall, well-dressed demon in a sharp British-style suit and tie, complete with round glasses, neatly combed black hair, dark skin, and a metallic silver tail ending in spikes. His eyes are typically squinted shut behind the glasses (sometimes revealed as jewel-like in certain forms).

Personality & Role: Demiurge is fanatically loyal to Ainz Ooal Gown (the protagonist), whom he constantly tries to impress by interpreting even the most casual statements as brilliant master plans. He delights in schemes, torture, human experimentation, and manipulating others, often running "farms" or operations that treat humans and other races as livestock or tools. Despite his cruelty, he is calm, polite, and gentlemanly in demeanor.

He's frequently disguised in the New World as the powerful demon lord Jaldabaoth to carry out large-scale operations while advancing Nazarick's goals.