The Spirit Waves are a dance group that consist of four female Ghosts in the episode "Ghost Princess." The group dances on a stage in a coliseum. Ghost Princess and Clarence watched their show together.
The Spirit Waves are female humanoid ghosts with no hair and simple faces, like most characters of the show. Their "feet" are in the form of heeled boots. Each is a different color: from left to right, they are blue, red, green, and gray. They are more anatomically accurate than most ghosts and other characters in the show.