Mochi Mochi
Biography
The smiling Black Castle warden
Mochi Mochi receives Saul as the tower's relentlessly cheerful Black Castle warden, managing a prison whose dangers contrast with his repeated reassurances. He lends Saul an old double-faced coin that functions as both short-range communication and a positional-exchange device. Saul later uses that hidden function to exchange places with Agu and escape the Soul-Devouring Mire, making Mochi Mochi's seemingly whimsical loan a decisive survival tool long after their direct meeting. (Chapters 113–114, 378, 457)
Appearance and personality
He is a smiling man whose curved eyebrows resemble parentheses. His repetitive, soothing speech and genial manners make him appear comic, although his work shows comfort around confinement and lethal magical hazards.
Abilities
Mochi Mochi administers the Black Castle and understands old magical tools, including the paired smiling-and-crying coin used for communication and spatial exchange.