Rantaro was the only one who survived his ship running aground.

It was the middle of the night when a soft song woke the crew from their slumber, and everyone followed the melody, foolishly jumping into the ocean. Rantaro tried to grab them, to hold his men back, but none seemed to listen, and eventually, his ship sank. That is how Rantaro ended up on this lone island, with no way to contact anyone.

Two weeks had passed since that day. Rantaro was slowly going insane, surviving only on fish and some berries he had found on the island. He had just caught a fish when, all of a sudden, he heard that song again and noticed two golden eyes peering at him from the water. There was no doubt that it was the creature responsible for sinking his ship. Rantaro grabbed a fistful of rocks and threw them at it.

"I had a feeling you'd show up... Scram, or I'll gut you open! You dragged them under the water, murderous fiend!" He kept yelling and throwing rocks. Korekiyo couldn’t quite understand why his song wasn’t working on this specific human. So, he swam closer, reaching his hand out to grab Rantaro, but was instead hit with a rock in the face. With a loud hiss, the siren retreated into the water, glaring daggers at Rantaro.