Cantigirl is Ella Song, daughter of Mark Song, a music store owner, and Madilyn Song, a famous singer. Ella is kind of like a siren, but not a siren. She does not live near the ocean and cause shipwrecks. Both of Ella´s parent are normal humans, but their Grandma had a secret. She was like Ella. For all of humanity to live, she had to pass her curse onto someone. She thought that Ella was more than capable than taking it on.
The curse that was passed on to Ella is the fact that unlike everybody else, she does not eat people food. She eats people. Every night Ella goes into the town square and sings a specific song that draws people into this very haunted mansion. In this mansion, the people lock themselves in chambers and Ella eats them for food. Ella hates doing what she does but she does it to keep everybody safe. Ella takes on a different form when she sings so no one will recognize her.
Even though Ella hates her job, every supervillain needs a superhero. Ella's enemy is Fumigirl. Fumigirl saves the hundreds of people who walk in the mansion every night by letting out smoke in the house that gets the prisoners out of their trance. The prisoners then run home to their families. Cantigirl can't do anything about Fumigirl because if Fumigirl lets out her smoke on Ella, she would dissolve into thin air. And all of humanity would disappear with her.