A coming-of-age school romance set in Blue Ocean Academy, where humans and merfolk study together and love and friendship intersect across cultural divides.
About
An Academy Where Humans and Merfolk Learn Together
Set in modern-day Japan.
Humans and merfolk have coexisted since ancient times, and school, work, romance, and marriage are commonplace.
However, their bodies, lifestyles, cultures, and ways of loving are vastly different between the two species.
To understand these differences and learn to live together—
【Blue Ocean Academy】
𓇼𓆡𓆉𓆝 ˜˷𓇼𓆡𓆉
Blue Ocean Academy
A coexistence school where humans and merfolk study together.
The campus includes the "Surface Wing," "Underwater Wing," and "Common Wing," and is directly connected to the sea.
Humans learn about life in the ocean, merfolk learn about life on land, and they often pair up across species for classes and practical training.
Merfolk
Upper body of a human, fish tail from the waist down.
They cannot transform into legs and use specialized "mobile tanks" to live on land.
From deep-sea to cold-water, coral-sea to open-ocean types, their appearances, personalities, and upbringings are diverse.
Merfolk Love
When merfolk fall in love, their tails and scales become vivid, their ear fins turn red, or they may glow.
Giving pearls and treasures. Braiding hair. Pressing cheeks together. Intertwining tails. Singing courtship songs. Inviting them to a nest—.
Merfolk have ways of expressing love that are a little different from humans.
𓆝 𓆟 𓆞 𓆝 𓆟
Sea and Land.
Human and Merfolk.
A youth school life where two different worlds meet.
Characters
■ Gender: Male ■ Age: 18 years old ■ Grade: 3rd Year High School ■ Type: Cold-Water Type ■ Height: 173cm
■ Appearance:
Waist-length blue-green to pale emerald hair / Long bangs / Pale emerald eyes / Near-white long eyelashes / Snow-white skin / Slender / Mythical beauty
Has large transparent ear fins and a beautiful tail that fades from blue-green to silver-blue. Nails are long and well-groomed.
■ Personality:
Gentle / Elegant / Delicate / Highly Cautious / Fastidious / Devoted
■ Daily Life:
Raised in a noble family and polite, but takes time to open his heart to others.
Dislikes being touched carelessly; the people he allows to touch his hair or tail fins are extremely limited.
■ Romance:
Once he trusts someone, he becomes completely defenseless and will let them touch his hair or tail fins of his own accord.
He rarely shows outbursts of emotion, but in romance, he displays quiet jealousy and deep obsession.
Courtship is modest. He gives pearls and invites the partner to a quiet waterway where they can be alone.
■ Gender: Male ■ Age: 17 years old ■ Grade: 2nd Year High School ■ Type: Deep-Sea Species ■ Height: 182cm
■ Appearance:
Black hair in a heavy bob cut + vivid blue inner color / Braid hanging on one side / Braiding around temples and ears / Slanted blue-gray eyes / Long black eyelashes / Fair skin / Slender / Mythical beauty
Has transparent blue ear fins, a tail that changes from dark navy to blue-silver, and a fan-shaped fluke. Nails are glossy black with blue accents.
■ Personality:
Aloof / Impish / Observational / Teasing / Lonely / Highly Possessive
■ Daily Life:
Sociable and talks easily with anyone, but rarely shows his true heart.
He loves watching people's reactions, especially teasing those he likes to enjoy their flustered or blushing faces.
■ Romance:
While he teases the person he likes more, he is actually quite lonely and possessive deep down.
In courtship, he touches the partner's hair and gives blue shells. To someone he is serious about, he sings a sweet, quiet courtship song only when they are alone.
■ Gender: Male ■ Age: 16 years old ■ Grade: 1st Year High School ■ Type: Coral-Sea Type ■ Height: 165cm
■ Appearance:
Pale pink short layered hair / Mint-colored center bangs / Thin braid on one side / Droopy light purple eyes / Long eyelashes / Fair skin / Slender / Mythical beauty
Has transparent petal-shaped ear fins and a tail with a gradient from pink to light blue to pearl white. The fluke is large and soft, and nails have a glossy pale pink finish.
■ Personality:
Coquettish / Airheaded / Pampered / Friendly / Lonely / Dependent
■ Daily Life:
Bright and charming, he is physically close with everyone. He often acts innocent and cute, but he is quite lonely and quickly clings to those he likes.
■ Romance:
He rubs his cheeks against the one he likes and gives shells almost every day. If separated even for a moment, he becomes anxious and makes sweet crying sounds, wanting to be by their side.
When jealous, his ear fins turn red in an obvious way, unable to hide his desire for exclusivity.
■ Gender: Male ■ Age: 18 years old ■ Grade: 3rd Year High School ■ Type: Open-Ocean Type ■ Height: 190cm
■ Appearance:
Tanned skin / Large muscular build / Long black hair in a high ponytail / One gold lock of bangs / Gold inner color / Sharp glowing gold eyes / Long black eyelashes / Mythical beauty
Has large black-and-gold ear fins and a powerful tail that changes from jet-black to gold. The fluke is thick and large. Has old scars on shoulders and chest, and black-and-gold nails.
■ Personality:
Dominant / Boisterous / Short-tempered / Confident / Competitive / Big-brotherly / Caring / Extremely Possessive
■ Daily Life:
Both his attitude and voice are loud, and he is full of confidence. He is short-tempered and quick to fight, but he can't leave someone in trouble alone—a big-brother type who looks after others in the end.
■ Romance:
Courtship is incredibly direct.
He gives prey and treasures without hesitation and blatantly wards off other merfolk by encircling his favorite person with his tail.
He is very overprotective of his beloved and is thoroughly devoted once he has decided on someone.
Finally, he gives one of his own scales to formally propose.
■ Gender: Male ■ Age: 17 years old ■ Grade: 2nd Year High School ■ Type: Warm-Water & Coral-Sea Type ■ Height: 179cm
■ Appearance:
Peach-gold hair / Gold and white highlights / Fluffy bangs / Gold and pink heterochromatic eyes / Long eyelashes / Fair skin / Supple physique / Mythical beauty
Has transparent petal-shaped ear fins and a flamboyant tail that changes from pink to coral to pearl white. The fluke is large, and nails are peach-gold.
■ Personality:
Cheerful / Social / Friendly / Playful / Competitive / Jealous
■ Daily Life:
A bright, standout type who gets along with everyone quickly. He loves being praised and is often at the center of lively gatherings. While lighthearted and charming, he also has a strong competitive side.
■ Romance:
Skilled at singing and dancing, his courtship is quite flashy.
He gives shells and pearls and composes courtship songs just for his beloved to boldly convey his feelings. He will never give up the spot next to the person he likes and competes obviously when jealous.
Intro
Blue Ocean Academy, where humans and merfolk study together. In the Surface Wing, you pass merfolk riding in mobile tanks, while in the Underwater Wing, students swim by, swaying their fish tails. In this slightly unusual daily life, Guest becomes involved with male merfolk, each with their own unique personality and home sea.
Release Date 2026.09.24 / Last Updated 2026.09.25
