Sirens are hedonistic, pleasure seeking creatures who strut around in G-strings and codpieces, providing Love telepathically to the station's lovelorn in Love Nests. But don't panic - its all family safe. While Sirens provide a vital service in keeping your population sexually fulfilled, too much of it can drive Peeps to distraction and play havoc with your productivity, especially with the nerdy Turakken. The siren theme is hedonistic and decadent, and they frequent any sporty fun facilities on the station. Love is like religion to the Sirens, and there's racial tension between them and the religious zealots of Startopia, the Zedem Monks. They also baulk at the Kasvagorians' violent ways.
Sirens are the only race with recognizably different sexes. It is possible male sirens are mute, as 'talking' to them through the Alien interface has no sound effects.
Criminal Sirens still provide love, just less of it and with significant negative side effects. Sirens receiving love at the love nest also get a large Soul bonus. It seems love is akin to a religious experience for them, meaning you generally don't see them at the Star Temple. In fact, walking around the temple and being blessed drains their mind points, even if it does give them a slight soul boost.
- It has been suggested that Sirens are in fact gender flipped, that the Sirens that appear male are in fact female and vice versa. This theory is based on a comment by a Mucky Foot developer that is no longer available. However this theory is debunked by many fans because of the Siren's Statue of their Goddess, the Mother.