Sure. King crab is a deep-sea creature, and it will carry companion creatures. Black worms are crab leeches, which will attach to king crabs to lay eggs. It is a normal phenomenon, which is harmless to human body and does not affect eating. King crabs, also known as stone crabs or rock crabs, that is, crustaceans of Stone Crabs, are not real crabs, and they are mainly distributed in cold seas.