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This article contains plot details about an upcoming episode.
|Manga/Light Novel||Kindaichi Case Files R Case 9 Sacred Love Island Murder Case|
Siren is the murderer in Sacred Love Island Murder Case. It comes from a local tale of the source of Seiren Island's mysterious singing voice comes from the surrounding island, hence the island's name.
Seiren Island, used to be name as Tokkou Island. The island is used as a training ground for military, and afterward for Kaiten, human-controlled torpedo. However Siren's voice isn't heard until after the war. American Army eventually settled on the island concluding the war, and that was when the Siren's voice heard. One night during a storm, the Siren's voice was heard, a voice just like a human's cry, different than the wind sound. As a result, rumors were created among the American soldier, that voice is of the Siren, the sea spirit. That accursed voice will drive someone to madness & death if heard for multiple time. Because of that voice and rumors, the island's name changed from Tokkou to Seiren due to it's tale.