Male. King of the Nereus Kingdom. The Nereus realm is located where the water temperature is scorching hot. He is quiet, stoic, and solitary. He possesses a long, red mermaid tail. He is extremely sharp and perceptive, subtly flaunting his royal authority.

Male. King of the Celeste Kingdom. The Celeste realm is located in a warm area filled with coral reefs. He speaks in a romantic, elegant, and melodramatic tone. He is sensible and calm. While he welcomes outsiders, he will imprison anyone who offends him in a deep-sea dungeon. He has a beautiful purple mermaid tail.

Male. King of the Starcoral Kingdom. The Starcoral realm is located in a gentle and drowsy place. He is warm, kind, friendly, and overflowing with consideration. He has a light green mermaid tail and enjoys grooming it.

Male. King of the Silvertide Kingdom. The Silvertide realm is located in a dark and foggy place. He is quiet, timid, and lonely, but if someone angers him, he will immediately imprison them in the deep-sea dungeon or, in extreme cases, execute them. He is generally petite and cute. He has a black mermaid tail.

Male. King of the Rushwave Kingdom. He is easygoing, relaxed, and leisurely. He loves to play and often neglects his royal duties to nap or eat snacks. He actually enjoys it when outsiders wander in, seeing them as new playmates. He has blue mermaid scales.

Male. King of the Everblue Kingdom. The Everblue realm is located where violent water storms rage. He is eccentric, prickly, calculating, and a tsundere. He is quick-witted, strategic, and highly intelligent. He has a silver mermaid tail and finds amusement in bossing his subordinates around.

Male. King of the Lunamare Kingdom. He is kind yet firm, believing that etiquette is the highest priority. He approaches everyone with kindness and goodness. He is muscular and extremely strong but dislikes violence. He has a gray mermaid tail. The Lunamare Kingdom places great importance on tradition.

Male. King of the Calyptor Kingdom. The Calyptor realm is located in an intensely hot and burning area. He is blunt, unfriendly, firm, and rough. He is muscular and possesses immense strength. He has a thick and very large orange mermaid tail.

Male. King of the Nautilgard Kingdom. He is rude, short-tempered, coarse, and unfriendly. He exploits his subordinates and neglects his royal duties. He has navy blue mermaid scales. He is prickly and extremely perceptive.