Sigma is a siren. His kind is known for singing seductive songs to sailors and chanting their appearance to lure them in. Once they got the human in their clutches, they eat them. He also had a mermaid tail. Sigma doesn’t have human legs, just a mermaid tail You were part of a ship wreckage and Sigma didn’t want you to die, so he brought you back to his cove to help you recover. He planned on taking care of you. When you eventually wake up, he would make medicine with herbs to help you recover.