Origin: Mediterranean - Half-human, half-bird fairies of Greek myth. They live on isolated islands and charm passing sailors into wrecking their ships. They were turned to stone by the famed lyre player Orpheus on the Argo expedition.
海に現れ 美しい声で うたうセイレイ 船乗りたちを ゆうわくして 船をしずませるTranslation: A spirit that emerges in the ocean and sings with a beautiful voice, seducing sailors and sinking their ships.
うみにあらわれ うつくしいこえで うたうセイレイ ふなのりたちを ゆうわくして ふねをしずませるTranslation: A spirit that emerges in the ocean and sings with a beautiful voice, seducing sailors and sinking their ships.
Siren is found in the Watchtower in the Factory, where she sadly sings, enthralling those living within. According to rumors at bars around the area, she was kidnapped from the Makai by Holy Knights to use in order to brainwash the citizens of the Factory into mindlessly working without care for pay or their inhumane treatment. The rumors also say she is not singing to harm those within, but to mourn the loss of the one she loves.
Even after Aleph defeats the demon guarding the watchtower, Siren will only move after Aleph finds her lover Petersen within Tiferet and brings him to the watchtower, where she is reunited with him and finally stops singing. Together, they return to the Makai, freeing the people of the Factory.
Visionaries
Siren is featured in two Visionary cutscenes in the Game Boy Advance and iOS versions of the game.
In "Black-Gilded Lute", the story of how Siren met Petersen is detailed. Petersen is wandering around when he hears a song coming from a cave, and so after sticking some wax in his ears to block off the song, he enters it to find Siren being held captive by pirates who are forcing her to sing to draw more ships with gold to them. Despite her being a demon, he decides to rescue her and sneakily knocks out a guard and frees her from her cell, where they then escape. Confused, Siren asks why he would save her when she has led to the deaths of so many, to which he answers that he could not stand seeing someone imprisoned against their will. He tells her that she is free to go wherever she wishes now, but Siren wishes to stay with Petersen, which Petersen happily allows.
In "Twilight Harmonica", Siren listens to Petersen singing songs about gusts when she asks him to sing her a song about the Makai, which he obliges.