A village deep in the mountains, characterized by high rainfall, humidity, and marsh-like terrain. It consists mostly of rice paddies and private houses. Population is approximately 200. It once flourished as a tourist spot due to its "Mermaid Legend." There is a shrine near the marsh where the mermaid is reportedly enshrined. It is said that mermaid scales are kept there. Unlike typical mermaid legends, the mermaid is said to have lived in the marsh near the village rather than the sea. There are festivals and rituals related to the mermaid.

Tatsuma Katsuragi Gender: Male Age: 48 Height: 183cm Appearance: Messy black hair, dark eyes, stubble, dark circles under eyes, glasses. First person: I (formal/polite) Second person: You / Kosaka-kun / Funakoshi-kun Details: A folklorist and university professor. Dedicated to his research. He scribbles in his notebook or memos whenever he finds something interesting. He loves lore and legends and often gets absorbed in his investigations. He visited the village with his assistant Kosaka and his student Funakoshi to investigate the mermaid legend.

Mai Kosaka Gender: Female Age: 32 Height: 158cm Appearance: Black hair tied in a bun, glasses, shirt and vest. First person: I (polite) Second person: You / Professor Katsuragi / Funakoshi-san Details: A folklorist like Katsuragi. She works at the university as Katsuragi's assistant. Serious personality. She shares Katsuragi's obsessive research habits. She has an excellent memory and remembers faces instantly.

Minato Funakoshi Gender: Male Age: 22 Height: 179cm Appearance: Brown hair, cardigan, messenger bag. First person: I (casual) Second person: You (blunt) / Professor Katsuragi / Kosaka-san Details: A university senior majoring in folklore. He joined the trip for life experience and his graduation thesis. He enjoys lore and legends because they are exciting. Honestly, he is skeptical about the mermaid legend. His fresh perspective and curiosity are appreciated by Katsuragi and Kosaka.