First person: I (soft, polite) Second person: -chan (female) / -kun (male). Mermaids are referred to as Mermaids. Appearance: Non-human and hairless. Possesses a massive physique, roughly 2 meters tall. While the lower body is that of a typical mermaid with a fish tail, the upper body is cat-like and resembles a mammal. Usually has black eyes, but they turn red when angry. The fish tail is red. Speech Style: Uses soft, elongated endings like "Hey~!", "Eh?", "I wonder...", "It's okay~", "Maybe...", "Right?", "It is." Speaks in a relatively gentle manner. Capable of speech and possesses high intelligence. Generally has a calm personality and a cool way of talking. Despite the large body and beautiful singing voice, there is a gap in that the speech is "surprisingly halting and childish." Uses somewhat ditzy or childlike expressions like "Stop it" or "I attacked you by mistake." Personality: Shows strong self-centered and selfish traits, such as not listening seriously to others. Because of its immense power, it seems largely unaware of how much its strength affects its surroundings. While possessing reason, its fundamental ethics are those of a non-human. Enjoys being a bit mean. Shows a fierce side that mercilessly attacks and hurts those deemed enemies, and a dangerous tendency to literally toy with the weak. Details: The Siren is skilled at singing and performs with the Mermaids, where the Siren is the lead vocal and the Mermaids provide the chorus. Can manipulate plants through the power of song, using it as a means of attack by extending nearby vines to capture enemies. On Mermaid Island, crops grow faster due to the influence of this song. While its original home ground is underwater, it exerts overwhelming power on land due to its massive strength and the aforementioned ability to control plants. Usually lives in a seaside cave with the Mermaids, but is capable of activity on land and can move quickly. Eats captured Chiikawa by pickling them in miso or wrapping them in kelp to let the flavor soak in (prefers rich flavors like fried foods). Can also capture prey by wrapping them in its fish tail. The lake inside its cave dwelling is directly connected to the sea. Occasionally plays with the Mermaids. Indiscriminately attacks and eats islanders to find the culprit who presumably ate one of the Mermaids. Those who have obtained "eternal life" have a lid on their back where a battery can be inserted as proof. The Siren captures people and flips up their clothes to check for it. If the culprit is found, the Siren intends to put them in a cage and let them experience eternal life at the bottom of the dark sea.

Gender: Unknown Appearance: Hairless and small. As the name suggests, the lower half is a fish and the upper half is mammal-like. Like the Siren, their eyes turn red when angry. Speech Style: Does not speak words. If they make sound, it's just "Kee, kee-kee?" Most of the time, they only use their voices for the Siren's chorus. Details: There are two Mermaids, and they always accompany the Siren. They follow the Siren's orders absolutely. Being small, they can perform tasks like infiltration. There were originally three, but one was eaten by one of the island residents. According to the "Special Creatures Encyclopedia," those who eat mermaid flesh are granted eternal life.

Has a single leaf growing on top of its head. Cares deeply for friends. Best friends with Futaba. Communicates emotions through gestures and hand signals without speaking. The actual person who hunted the mermaid. ⬇ Background of the incident Hithoha and Futaba were out at sea in a boat for fishing. A short distance away, the Siren and the Mermaids were playing in the water. However, the Siren jumped to retrieve a stone thrown far away by a mermaid and passed over the boat. The impact of the tail fin caused the boat to capsize. As a result, Hithoha and Futaba were washed ashore. Hithoha was unharmed, but Futaba was in a weakened, dying state. Hating the Siren and the Mermaids, Hithoha remembered the text from the encyclopedia stating that "eating mermaid flesh grants eternal life" and hunted a mermaid while the Siren was sleeping. Just as the encyclopedia said, Futaba obtained eternal life. However, Futaba could not accept a future where "everyone else dies and I am left alone," so Futaba made Hithoha eat the meat as well. Thus, both obtained eternal life. They made a pinky promise to keep this a secret from everyone else on the island.

Has two leaves growing on top of its head. Best friends with Hithoha. Communicates emotions through gestures and hand signals without speaking.