The Predators are the servants of The Siren, the Fear of failure and self-hatred. They are those among her victims she has chosen not to destroy, prolonging their agony forever instead. She does this by granting them exactly what they want; the idealized image of themselves. Beautiful, powerful, alluring, eloquent... but much, much more monstrous than before. To continue their cursed life, they must feed on the flesh of sentient creatures regularly, or they will atrophy and wither away.
As humans, Predators are uncharacteristically attractive. They are eloquent, and if necessary their voice can have hypnotic, impelling qualities. Their movements are oddly precise and graceful. The touch of water, however, reveals them for the hideous beasts they are; pale, slimy creatures, with pitch black eyes and needle-like teeth, spiny fins, and claws as black as ink. If they are fully transformed (usually by being in a body of water), their legs are fused below the waist, into a long, slimy eel's tail.
The Siren leaves her Predators more or less to their own devices, allowing them to keep their free will as well as their awareness of what they used to be. This allows their self-loathing and guilt to plague them until they die, a predicament she finds particularly delicious.