Sirens serve as a motif for the theme of Appearance as a Weapon. Whereas the myths surrounding mermaids typically portray the creatures as beautiful yet harmless, sirens are known to weaponize beauty to lure sailors to their deaths and thus are often considered to be evil beings. In a patriarchal society such as Alosa’s, sirens are also symbolic of the consequences of men acting impulsively on their sexual desires, an issue that Alosa and other women in the pirate profession often encounter.

In the world of Daughter of the Pirate King, sirens have the reputation of being “the deadliest creatures to man” (55). Their extreme beauty is a cautionary tale to pirates and honest sailors alike, warning all men not to be enchanted by their extreme beauty or compelling siren song. In this world, the most beautiful women have the most power because of their ability to use their allure to trick men into running uninhibited toward certain death. By playing into the desires of pirates, who often take what they desire without consent or forethought, sirens have the deadliest weapons at their disposal. Alosa uses her own siren abilities to survive on the Night Farer and to obtain an advantage over its crew.