These sea creatures are named for their belief that they are descended from the household of the Great Race, who were left behind when the Great Race rose up to heaven long ago.
In the sea they curl up into a ball, about the size of a loaf of bread. They travel in clusters of a few Companions. Each cluster rides within a skin that appears to be that of a dolphin. On land they hide the skin, uncurl, and grow, becoming a creature indistinguishable to a human.
At times they speak of their false dolphin skin as if it was an actual body, rather than a disguise, and of each cluster as a single being. However they seem to regard themselves as separate while on land.
They never forget the location of their skin and, if it is moved, will have a dim sense where it is. If the skin be destroyed, they seek out another 'family' and ask to cluster with them. It is unknown what happens if a cluster gets too big, or indeed how they reproduce.