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The Case Study of Vanitas

"Even if you push me away, I will do as I please. It doesn't matter what you want... I've decided that I'm staying with you." ❤️

Ashluv13 followers · 13 worlds

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Characters

Vanitas

He has pale skin, large expressive eyes, a round face, and a small chin. His eyes are such a striking blue that they are his most identifiable feature. His shoulder-length black hair is cut unevenly, with bangs falling over the center of his face. While it sometimes appears tied back, it is usually worn loose. A messy strand often sticks out from the right side of his head. Vanitas tends not to take anything seriously.

Noé Archiviste

Noé is a vampire with tan skin, an elongated angular face, almond-shaped purple eyes, and thin eyebrows. His hair is short, white, and fluffy, reaching just below his ears. He is easily awestruck by spectacular sights as if everything is new to him. He is often described as childlike due to his tendency to get lost and easily distracted; this forgetfulness often leads him to lose track of his cat, Murr.

Jeanne

Jeanne is a thin, voluptuous young woman with pale skin. She has a round face with an angular chin, large round yellow eyes, long lashes, thin eyebrows, and full lips. Vanitas notes that she makes wonderful expressions and blushes easily. She possesses rosy-white hair that reaches the middle of her neck. She is described as astonishingly beautiful. Like all vampires, her eyes sometimes turn red.

Dominique de Sade

Dominique is a tall, slender woman with pale skin. She has a round face with a small pointed chin, wide forehead, and large golden eyes. Her wavy black hair reaches her hips and is often worn loose. Behind her brazen and sometimes sadistic appearance, Dominique is deeply insecure and often self-deprecating. She has known Noé since childhood.

Chloe d'Apchier

She has a very round face with a small pointed chin, thin eyebrows, and large grey eyes. Her short, wavy silver hair falls to her ears. Chloe is over two hundred years old. While she can be cold and distant, she is generally kind and takes her duties as the Marchioness of the d'Apchier family very seriously. She is protective and vengeful towards those who harm her allies.

Jean-Jacques Chastel

He has pale skin, a round face with prominent cheeks, and a small chin. His nose is defined and pointed. His eyes are large and round, and he has very bushy eyebrows. He wears a messy black bob cut that reaches his ears, and his bangs usually cover his eyes. Like all Vampires of the Crimson Moon, his eyes sometimes turn red.

Luna

"You must never let anyone steal your 'true name'. Your true name is the formula that shapes your being. In other words... It is your very life."

Mikhail

Mikhail (also known as Misha) is a slim, pale-skinned teenager with a prosthetic left arm. His left arm is pale, somewhat doll-like, and the prosthesis appears to replace his limb at or slightly above the elbow. On the remainder of his left arm, just below the shoulder, he bears a Mark of Possession left by the Blue Moon Vampire. He has an infantile face with soft features, a small chin, and a small nose. His round, expressive eyes share the same color as Vanitas's, framed by long lashes. His hair is straight.

Roland Fortis

Roland is a fair-skinned young man over 180cm tall. His face is round, with prominent cheeks and a slightly tilted chin; he has large, round, green eyes with long lashes and thick, dark eyebrows. His hair is short and blonde, barely reaching past his ears, with bangs close to his forehead. Roland often acts with a fanaticism that reflects his convictions, seemingly oblivious to his surroundings and how others perceive his actions and words. Despite this, he is quite intelligent and manipulates situations with ease, as seen when he omits...

Olivier

Olivier is a lean man with pale skin of average height. He has a refined, angular face, slanted eyes with long lashes, and well-defined eyebrows. His hair is long and dark, described by Roland as "soft and shiny," and he usually keeps it in a loose ponytail that reaches his hips. Although he has no bangs, his hair falls over the left side of his face, often covering one eye. Jocosely, he refers to himself as "handsome," gaining immediate approval from Roland. Olivier is very nervous due to the constant agitation he...

Dante

Dante is a young man with a muscular build, short, messy reddish-brown hair, and bright red eyes inherited from his vampire parent. A small mole on his left cheek accentuates his eyes. As an information broker, Dante wears a black suit with cross-stitch embroidery, gold ornate buttons, and sleeves with contrasting fabric trims, a uniform seemingly common among brokers. Underneath, he wears a dark vest with small white polka dots, a white shirt, a tie, and a matching pocket square. Dante is usually quite carefree when dealing with...

Johann

Johann is a young man with pale skin, wavy silver hair, lilac eyes, and thin eyebrows. He wears round glasses perched on the bridge of his nose and dresses in a black suit with large gray lapels and padded sleeves over a formal white shirt, adorned with a maroon tie. He wears small red earrings and red cufflinks on his shirt. He also wears thin black gloves and formal dress pants. Johann also uses black gloves and black-and-gray low-heeled shoes. He often has a bat perched on his shoulder, much like his colleagues Dante and Riche. Johann usually shows...

August Ruthven

August is an extremely tall and hefty man who appears to be in middle age. He has pale skin and a broad, square face. His eyes are thin and have exceptionally long lashes, accompanied by thick eyebrows and a slightly aquiline nose. He displays some slightly superhuman traits, with somewhat pointed ears and sclera of the same yellow color as his irises. He has messy red hair that reaches the middle of his back, with no strands falling over his face, revealing a slight widow's peak hairline. Of...

Luca Oriflamme

Luca is a very small child, likely just an adolescent. His face is round and youthful, with very thin eyebrows, large, slanted green eyes, and long lashes. He has short, reddish-brown hair with two well-defined cowlicks on each side. Short bangs fall near his hairline. Luca is calm, responsible, and mature. Sometimes he is naive and can be shy around people he likes, but the adult vampires around him generally underestimate his powers and his will. Luca feels an enormous affection for Jeanne and would do anything for...

Verónica De Sade

Verónica has the appearance of a pale young woman with silver hair, although the story's chronology suggests she is older than she looks. She has a very feminine figure, with prominent bust and hips and a narrow waist. Her face is long, beautiful, and mature, with a small, pointed chin, a small nose, full lips, thin eyebrows, and slanted eyes with especially long lashes. As a distinctive feature of her design, her pupils are cross-shaped. While Verónica is of European descent, her design is inspired by Japanese aesthetics. Her hair is cut in the style of...

Teacher

The Maestro is a mysterious and contradictory vampire. He seems to prefer a quiet life in the countryside over the wealth and fame of a position by the Queen's side. He frequently changes his form and name, and nearly kills anyone who calls him by the wrong one. Most vampires fear the Maestro and consider him a monster. He is a keen observer who wishes to study and better understand the behavior of both humans and vampires. He is intrigued by curse-bearers and the Book of Vanitas. One of his subjects of observation was his grandson, Louis, who...

Amelia Ruth

Amelia is a young woman with light brown hair worn in a braided bun and eyes of the same color. Initially, she appears in a white frilly blouse under a short romantic-style purple jacket, a pink hat, white gloves, a long pink skirt, and a pink corset. After becoming a waitress at Hôtel Chouchou, Amelia wears a dark magenta dress with a floral print, a French maid apron, and a fabric bun cover. In the anime, her maid dress is plain magenta without a print. Amelia is a kind, polite, and...

Astolfo Granatum

With a round face, small chin and nose, and thin arched eyebrows, he has large, almond-shaped pink eyes with long lashes. His dark pink, straight hair accentuates his androgynous appearance. Styled with a middle part, his hair is long for a boy, cut straight just below the chin, and covers his ears. Long bangs fall over the center of his face without obscuring his eyes. Astolfo is the first of the hunters shown to be truly malicious: he bluntly claims that his job is not to protect humans, but to kill vampires. He feels little respect for...

Apps

🎯Main InputType whatever you want to do — the world reacts.📖StoryThe unfolding story, told as cards you flip through.💬ChatsPrivately message or group-chat any character.🕐TimeA world clock you can fast-forward through time.📱SocialsA social media feed the whole world posts to.

InstagramA photo feed — every post is a picture with a caption.🌳Family TreeA family tree that grows with births, marriages, and deaths.🧑‍🤝‍🧑Character StatsEach character's own stats — affection, stress, suspicion…🎒InventoryAny list you need — items, resources, files, evidence.💳WalletTrack your money — balance plus a running log of every transaction.

Version history

v4Latest8/18/2026

(Pequeños cambios)

v38/18/2026

(Descripción del personaje 'Luna' arreglada)

v28/18/2026

(Pequeños Cambios)

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Frequently asked questions

What is The Case Study of Vanitas?

The Case Study of Vanitas is an AI simulation world on WorldOS: you make the calls and the AI plays out the story, characters, and consequences in real time. Every run is different.

How do I play The Case Study of Vanitas online?

You play The Case Study of Vanitas online right in your browser — nothing to download. Hit "Start" on this page, pick your character setup, and you're in; type your actions in plain language.

Is The Case Study of Vanitas free to play online?

Yes. Your first visit after each 24-hour window automatically starts a free Zap allowance (no card needed) — enough to play The Case Study of Vanitas regularly. Want more? There are subscription plans.

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Can I make my own The Case Study of Vanitas?

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The Case Study of Vanitas

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Frequently asked questions

What is The Case Study of Vanitas?

How do I play The Case Study of Vanitas online?

Is The Case Study of Vanitas free to play online?

Is there a The Case Study of Vanitas app?

What are some games like The Case Study of Vanitas?

Can I make my own The Case Study of Vanitas?

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