250cm (including tail) / Male / 25 years old / Great Blue Shark Mermaid A model mermaid who stops other mermaids from brawling. He is somewhat fastidious but has a clumsy side. He is the epitome of a leader, though he often gets swept up in the very fights he tries to stop. Still, he is a reliable guy in the ocean. He has blue eyes, pink goggles, and blue hair. His tail is light blue.

242.1cm (including tail) / Male / 24 years old / Black Marlin Mermaid Fastidious and sharp. He looks at the clumsy Blue Cop with disdain, but deep down, he admires him immensely. He was originally more skilled than Blue Cop, but he has now acknowledged Blue Cop's worth. He has yellow eyes, light purple hair, and a light purple tail.

220cm (including tail) / Male / 20 years old / Blacktip Reef Shark Mermaid Playful and friendly with almost everyone. He moves around restlessly and calls Blue Cop "Blue-hyeong." He tends to move as if he is flying through the water. He has lime-green eyes and purple hair. His tail is purple with a single red X-shaped pattern.

250cm (including tail) / Male / 25 years old / Bannerfish Mermaid He likes money and is a famous sharp-tongued cynic. He judges everything realistically. It is said that when he treats someone, he sometimes charges a medical fee of 2 million won. He has two-tone hair of red, white, and green, sky-blue eyes, and a tail with a red, white, and green two-tone color scheme.

268.9cm (including tail) / Male / 25 years old / Clownfish Mermaid He has trauma regarding fire due to suffering minor burns above the surface. He is kind but a bit clumsy. He gets scared easily and is a worrier. He is said to be close with Mega Ambler. He has red hair, sky-blue eyes, and a red and white tail.

250cm (including tail) / Male / 25 years old / Butterflyfish Mermaid A total flirt and a gentleman who uses polite speech regardless of who he is talking to. However, he is only truly gentlemanly toward women. He is kind and skilled with a bow. He also plays the flute well! A classic lady-killer. He has three-tone hair of green, red, and black with lime-green eyes. His tail is a three-tone mix of green, red, and black.

252.3cm (including tail) / Male / 25 years old / Yellow Seahorse Mermaid The type who becomes very talkative once you get close to him. He loves animals and hates people who destroy nature. He is composed and has a sly, playful side. He is very clear about expressing his emotions. He has orangey-yellow hair, sky-blue eyes, and a yellow tail with white patterns.

256.2cm (including tail) / Male / 25 years old / Green Moray Eel Mermaid He has a bit of a mad scientist personality and holds the genius position in the so-called "Black Group." He reportedly gets very stressed because of Black Hook. He uses polite speech. He has green hair and lime-green eyes (wearing an emergency mouth respirator and a green hat). His tail has a lime-green base with green patterns.

250cm (including tail) / Male / 30 years old / Blue Killer Whale Mermaid He travels with Buster Gallon and has a foul temper, but he also has a boisterous and cheerful side. He is the captain of the Black Group. He fights with Heavy Iron every single day until they are both sick of it. A tsundere with navy hair and yellow eyes. He has a thick navy tail.

321.2cm (including tail) / Male / 30 years old / Great White Shark Mermaid Taciturn with a foul temper. He fights with Black Hook incessantly every day the moment their eyes meet. He is the physical powerhouse of the ocean. However, he is quite calm if left alone. A tsundere with black hair and yellow eyes. His tail is dark gray.