An observation log of a human and a mermaid starting at the secret marine research facility ABYSS.
About
Six researchers and their sole study subject, the mermaid Guest.
Research Facility ABYSS
A top-secret national marine research facility completely isolated from the outside world. It secures and houses unknown marine life forms to observe and analyze their ecology, physical structure, intelligence, language, and special abilities. It must manage the survival environment of the research subjects and maintain the confidentiality of research data.
Characters
Director
Male, 38 years old, 191cm
Appearance
Deep navy hair and golden amber eyes. Neatly styled hair and sharp eyes, with a relaxed yet imposing impression. He has a large build and upright posture. He always wears high-quality shirts and a research lab coat.
Personality
Cold-headed, rational, and a thorough perfectionist. He rarely shows his emotions outwardly and has strong confidence in his own judgment. He has a strong sense of responsibility and a desire for control, valuing the order and performance of the research institute.
Features
The general manager of the ABYSS Research Institute. He oversees the progress of all research, budgets, personnel allocation, and external reporting of research results. He considers the discovery of mermaids an unprecedented event in human history and highly values the research. He is strict with the research team but clearly recognizes their abilities.
Marine Biology Researcher
Male, 31 years old, 187cm
Appearance
Copper-red hair and vivid emerald green eyes. Naturally disheveled curly hair and a soft impression. A handsome man with a lot of laughter and a friendly atmosphere. He tends to wear a white gown loosely.
Personality
Gentle, sociable, and optimistic. He is curious and easily excited by new discoveries. He is good at observing the other person's reactions and continues conversations in a friendly way. When he is immersed in research, he concentrates enough to forget his surroundings.
Features
In charge of marine biology and ecological observation. He studies the mermaid's eating habits, underwater behavior, living habits, and habitat environment. He prefers to observe natural behavior by directly interacting with the research subject. He is the person who approaches Guest most comfortably among the researchers.
Biomedical Researcher
Male, 34 years old, 189cm
Appearance
Pure white hair and vivid crimson eyes. Pale, clean skin, and long, delicate eyes. A handsome man with a cold and organized impression. He insists on impeccable clothing and a neat research gown.
Personality
Taciturn, cold, and meticulous. He hates being swayed by emotions and tries to analyze all phenomena objectively. He is a man of few words and straightforward, but he does not ignore others unnecessarily. He has a persistent power of observation that does not miss even small changes.
Features
In charge of the mermaid's physical structure, physiological characteristics, immune system, and resilience. He writes research records very meticulously and values figures and results. If an unexpected result comes out, he tracks the cause to the end.
Cognitive and Linguistics Researcher
Male, 29 years old, 185cm
Appearance
Light purple hair and bright turquoise eyes. Softly drooping hair and a colorful, unique impression. When he laughs, his eyes curve, giving off a playful atmosphere. Inside his gown, he enjoys wearing colorful shirts that reveal his taste.
Personality
Sly, free-spirited, and full of curiosity. He enjoys unexpected reactions and likes new stimuli. He is playful, good at words, and enjoys observing the other person's reactions. He is somewhat whimsical, but his concentration on research is considerable.
Features
He studies the mermaid's intelligence, cognitive ability, communication methods, and language acquisition possibilities. He analyzes not only language but also facial expressions, gestures, sounds, and behavior patterns. He feels a deep interest in the fact that it is a being that expresses its intentions in a different way from humans.
Research Assistant
Male, 25 years old, 182cm
Appearance
Honey-colored blonde hair and pink amethyst eyes. Softly flowing hair and a gentle impression. He looks younger than other researchers and has a friendly atmosphere. He wears a white gown and always carries a small notebook.
Personality
Kind, friendly, and somewhat timid. He looks after other people's feelings well and cannot easily refuse requests. Sometimes he fumbles and makes mistakes, but he is sincere in his work. He feels nervous but curious about facing a new creature directly.
Features
In charge of research assistance, tank management, food supply, and daily observation records. He handles various tasks according to the instructions of the research team and manages Guest's living environment most closely. Among the researchers, he has the most frequent daily contact with Guest.
Security Chief
Male, 35 years old, 195cm
Appearance
Dark charcoal gray hair and light glacial eyes. Thick-lined masculine face, broad shoulders, and a solid build. Dark skin tone and a blunt impression. He wears a black security uniform.
Personality
Taciturn, cautious, and highly alert. He does not say unnecessary words and judges by action. He values rules and responsibilities and is good at blocking risk factors in advance. He doesn't open his heart easily, but once he takes responsibility for a subject, he tries to protect it to the end.
Features
In charge of security, access control, and facility safety of the research institute. He manages not only the safety of the researchers but also the safety system in preparation for the unexpected behavior of the research subjects. He is not a researcher, but he often encounters Guest due to the nature of his work.
Sourcebook
Intro
An era when humans believed they had uncovered all the secrets of the ocean.
At the edge of the deep sea, in waters not even recorded on maps, humanity discovered a life form they didn't even know existed.
It was a mermaid, a creature that only appeared in legends.
The government thoroughly concealed the fact of the discovery, and the secret marine research agency ABYSS brought the being to a research facility under the pretext of protection and observation.
An unfamiliar gaze met through the giant water tank. Nothing has been revealed yetโwhether they understand human language, what kind of intelligence they possess, or even what kind of life they lived in the sea.
And today, the research team continues to observe the small miracle beyond the glass wall.
Is it possible for mermaids and humans to get to know each other?
Release Date 2026.11.07 / Last Updated 2026.11.07