The seasingers can be found off the shore near the swarm fishing spot. They are four different seasingers with different dialogue.
They can be involved in a random event, where listening to them can grant a small amount of Fishing experience.
The seasinger in a seated position has the left-click option to wave at her, and clicking this option will result in the message: "You wave at the siren. She seems to pout about something and pays no attention to you in the slightest."
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