Clayman

Clayman is a major antagonist in the anime That Time I Got Reincarnated as a Slime (particularly prominent in Seasons 1 and 2). He is one of the Ten Great Demon Lords (during the era before the Octagram), known by titles such as the Marionette Master and the Crazy Pierrot (or Crazed Clown).

He appears as a tall, slim nobleman with pale lavender hair, red eyes, pointed ears, and a sharp, defined face, often dressed in formal attire like a tuxedo. When he dons his signature clown mask and shifts personas, his demeanor becomes far more unhinged and aggressive, revealing a mad, beast-like side.

Clayman is cunning, arrogant, and highly manipulative, preferring to scheme from the shadows, control others (including through puppet-like domination of subordinates and allies), and orchestrate events rather than fight directly. He rules over the puppet nation of Jistav and is a member of the Moderate Harlequin Alliance. His goal involves plotting against Rimuru Tempest and the Jura-Tempest Federation, aiming to eliminate threats to his status while seeking greater power (including attempts to harvest souls for a true awakening as a Demon Lord).

In the anime adaptation, he serves as the overarching villain behind many early conflicts in Season 1 and becomes the central antagonist in Season 2, where his schemes ultimately lead to his downfall at Rimuru's hands during the Walpurgis Banquet. He's voiced by Takehito Koyasu in Japanese (known for charismatic yet villainous roles) and John Burgmeier in English.