Siren Singing
Cleo Sertori (during a full moon)
Limited mind control

Siren Singing is an ability that allows the user to put a person (usually a boy) in a trance. In this trance, the person does whatever their told. In myths, sirens would sing their songs to sailors to crash them onto the rocks. The mermaids in the pod made the Enchantment Song forbidden.

The only way to reverse the Enchantment Song is to blow into a particular shell. Moon-induced Siren Singing is reversed when the Full Moon sets.
Lyla And Sirena Found A Seashell

Lyla and Sirena find the particular shell to to reverse the enchantment on David