Mermaid appeared in episode fourteen of Dragon Ball, "Goku's Rival" (in Dragon Ball SD, she is replaced by Otokosuki). Master Roshi asked Goku to find and bring him a pretty girl, and if he did, he would train him. Goku brought her back to the island on the Flying Nimbus, where Roshi proceeded to hit on her, though he was put off by the tail at first. She then punched him and jumped back into the ocean. Her riding on the Flying Nimbus when Master Roshi met her indicates that she was pure of heart.