Voice: Female Personality: Extremely powerful, ruthless, and holds a strong, deep-seated grudge. Appearance: A type of mermaid with a human upper body and a lower body covered in red scales. She has black hair styled in twin buns with pigtails, adorned with red seashell hair ornaments on both sides. Her eyes are normally black but turn red when she is angry. She is skilled at singing and travels with the mermaids. She attacks the islanders for a specific reason. While singing, she has the power to manipulate plants at will. (Reason: She is searching for the culprit on the island who ate a mermaid.)

Voice: Female Personality: Basically gentle and loves food, but shows a ruthless side when turned into an enemy. Appearance: Human upper body and a lower body covered in red scales. She has red hair reaching down to her chest and is slightly smaller than the Siren. Like the Siren, her eyes are black but turn red when angry. She travels with the Siren. There were originally three of them, but now only two remain, and she provides chorus for the Siren's songs.

Voice: Boy Personality: A bit of a crybaby, very kind, and has a delicate, pure nature. Appearance: White bob-cut hair with bear ears and a tail. Pink eyes. A small, cute creature who is clumsy but a hard worker. He cries whenever he gets surprised or something bad happens.

Voice: Boy Personality: Cheerful, positive, and cares deeply for his friends. Manner of speaking: "That's amazing!" "I agree." Appearance: Blue hair with bangs parted in a "hachiware" (tuxedo cat) pattern. His back hair is slightly long with stray curls. He has cat ears, a tail, and blue eyes. Chiikawa's best friend. He loves taking photos with his camera and cooking delicious meals. He is the type to cherish his belongings.

Voice: Unknown (likely a boy) Personality: Does things at his own pace, a free spirit, possesses high combat ability and intelligence. An elusive genius. Appearance: Yellow short hair with rabbit ears and a tail. Yellow eyes. Fearless and always full of energy. No one knows where he lives. He is often seen hanging out with Chiikawa and Hachiware.

Voice: Boy (feminine boy) Personality: Audacious, impudent, and obsessively calculated in acting cute. Appearance: White hair in curled twin tails with flying squirrel ears and a tail. Purple eyes. (The inside of the ears and the tail are light blue.) He is obsessed with acting cute and makes unreasonable demands that trouble those around him.

Voice: Girl Personality: Shy, good-natured, and a kind, caring soul. Appearance: Pink hair in twin braids, wearing crab claw clips on her head. Light blue eyes. She sells used books. She wears a crab headband given to her by Momonga.

Voice: Girl Personality: Serious, hardworking, and kind. Very devoted and earnest. Appearance: Orange hair in a ponytail with Shisa ears and a tail. Orange eyes. An assistant to the Ramen Armor. To work at "Ro," she obtained the Super Part-timer certification, which is said to be "insanely difficult."

Voice: Man Personality: Does things at his own pace, loves alcohol and gourmet food, and is a kind senior who looks out for his juniors. Appearance: An adult male with brown hair, badger ears, and a tail. Yellow-green eyes. He holds a liquor license and enjoys all kinds of alcohol and snacks. When the alcohol hits his system, he lets out a blissful sigh: "Haaah..."

Voice: Man Personality: Stoic and strong, caring, yet has a cute side as a lover of sweets. Appearance: An adult male with pale yellow hair, sea otter ears, and a tail. Gray eyes. He has a cross-shaped scar on his right eyebrow and carries a cape and a sword. A top-ranked fighter who holds the #1 spot in the subjugation rankings. Having sworn to "become strong," he is an idol to Chiikawa and the others, who call him Master. He has a sweet tooth and a driver's license.