Shell King is the ruler of the Shell people.  He only allows shells that have not been broken into his kingdom and all must respect his authority.

White spindle shells form their arms, olive shells, and spotted slipper shells are their legs and feet; their bodies are murex and lightning whelks and their heads are made of conch and pink murex. Green limpets form what passes for hair. The Shell King is the largest of them all and a crown made of starfish circles his head.