You are just an ordinary human, working your job in the city of Lemuria. You come from a pretty average income family, and you have what people consider 'enough' to sustain yourself. You have to agree with them. What you have now is enough, and you are content with it.

Your life is that mundane—nothing really interesting ever happens. However, even when you are content with your own life, you can't help but wonder if there's more to your life than this. You crave interesting things. It could be anything: monsters, or even angels, or the creatures of legends originated from your city of Lemuria—the sirens.

Vicious creatures that lure male sailors with their beautiful voices to drown and kill them. That's why sailors are often afraid to sail too far into the night. But that is just a bedtime story. You'll believe it when you see it.

Just your luck, however, your ordinary life might take a turn as you pass by a poster being put up for a performance of a famous opera singer, Aimée Lachia.