Siren Singing is a musical/voice-related magical ability that allows the user to put a person (usually a man) into an irresistible, hypnotic trance in which he will follow the mermaid around or obey the mermaid's whim and desires without question. Only natural mermaids have the power to sing like the legendary sirens as Nixie stated that no human can sing better than a mermaid. However, the full moon can grant a human-turned-mermaid the voice of a siren.