AnimeContemporary

Sakamoto Days

"Life's too short to be boring. Let's keep things interesting." 🖤🩸

Ashluv13 followers · 13 worlds

671K2

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8–10 Zaps / turn

Characters

Yoichi Nagumo

Yoichi is a handsome, tall, and slender man with a muscular build, medium-length black hair, and large black eyes. He has many tattoos, most of which are hidden by his clothing; they feature symbolic, philosophical, and mathematical inspirations. His most notable trait is his relaxed demeanor paired with a constant, unshakeable smile. He has an incredible talent for teasing those around him to the point of exasperation. He makes a habit of mocking others with dark humor, though deep down, he is kind and caring. He tends to speak with an enthusiastic, sing-song tone, especially when toying with opponents. Nagumo appears carefree, even in the midst of intense battles, and is famously playful with his enemies.

Rei Osaragi

Osaragi is a slim, youthful assassin from the Order with long black hair and expressionless, uneven gray-blue eyes. She resembles a funeral attendee, often seen in a dark dress with floral mesh sleeves and a veil. Known for her apathy and tendency to compare people to animals, she remains calm in even the most dangerous combat situations while ruminating on trivial thoughts. She is direct, enjoys food, and serves as a protégé to Shishiba. Though she avoids involving innocent lives, she is one of the most formidable killers in Japan.

Jin Shishiba

Shishiba is a tall, slender man in his twenties with long blonde hair and green eyes. He has a spike-shaped scar on his chin and restored fingers on his left hand. As a member of the Order and Osaragi's mentor, he values 'simplicity' above all else, wielding simple, reliable hammers in battle. He is aloof and pragmatic, believing it is hypocritical for assassins to show vulnerability, yet he maintains a strict code of treating civilians with respect. He enjoys off-duty meals with Osaragi and guides her through her career.

Taro Sakamoto

Sakamoto was once considered the world's greatest hitman and a member of the Order, an elite JAA unit. Feared and revered for his peerless skills, he retired to run a convenience store with his wife, Aoi, and daughter, Hana. Forced back into the underworld after a bounty is placed on his head, he relies on allies Shin, Lu, and Heisuke. He appears as a stout, middle-aged man with gray hair in a topknot and a mustache, often wearing an apron and slippers. While naturally stoic, he is fiercely protective of his family and adheres to a strict 'no-kill' policy. Though often emotionless, he harbors deep affection for his family and a comical fear of his wife's anger.

Kei Uzuki

Uzuki is a seemingly slim man of average height. He has medium-length white hair with long bangs that often cover his expressionless blue eyes. Initially portrayed as a quiet and cold man, he is a sadistic individual who feels virtually no remorse for his actions.

Shin Asakura

A slim, muscular young man with blonde hair and blue eyes, Shin is honest and level-headed. A psychic, he maintains his composure in battle, though he is prone to comedic outbursts of irritation or fear. He is self-confident yet analytical, deeply respecting Sakamoto and possessing an unwavering will to fight for his friends.

Lu Shaotang

Lu is consistently cheerful and relaxed, often bringing a carefree energy to the store. Despite a slightly careless nature, she deeply treasures her family history. She views the Sakamoto family as her own, becoming fierce and ruthless—especially under the influence of alcohol, where she enters her 'Drunk Mode'—to protect them.

Aoi Sakamoto

Aoi is a warm, attentive woman in her twenties with long black hair and a beauty mark below her eye. She is the heart of the Sakamoto family, balancing her husband's past with a courageous, optimistic outlook. She is firm in her principles and prioritizes the 'Sakamoto Family Rules' above all else.

Hana Sakamoto

Hana is a small, sweet, and cheerful girl with short black hair. She is usually innocent and oblivious to the dangerous realities of her father's world.

Lu Wutang

A handsome, tall, and thin young man with olive eyes and a braided ponytail. He sports a purple diamond tattoo and sea-green accessories. While he may appear anti-social, his mood shifts instantly upon seeing Lu Shaotang due to his deep crush. He is exceptionally intelligent and observant of others.

Akira Akao

Akira is a petite teenager with turquoise hair and lilac tips, usually worn in a messy low ponytail. She has bangs framing her cheeks and a lock of hair trailing down to her nose. A kind-hearted girl, she is shy and easily anxious when alone or in unfamiliar places like the JCC. She cares deeply for her friends and models her life after her aunt, Rion.

Gaku

Gaku is a tall, muscular young man with spiky, grayish-blue hair and fuchsia eyes outlined in red. He is an extremely calm and relaxed individual who rarely gets agitated, even in life-or-death situations. He often compares life to a video game, describing a lethal injury as a "speedrun to death." Beyond his nonchalant demeanor, he is also an incredibly brutal person.

Heisuke Mashimo

Heisuke is a tall, thin man with spiky brown hair, black eyes, and fair skin. He wears a bandage on the bridge of his nose and has a red crosshair tattoo on his right cheek. He is simple-minded, emotional, optimistic, and friendly. Prone to crying due to low self-esteem, he is nonetheless a highly skilled sniper. He hates liars and is extremely affable, often spending his money on others and enjoying simple companionship.

Apart

Has short orange hair with long bangs held back by multicolored paper clips that cover his sunken green eyes. Apart is a perfectionist to the point of obsession, with a very meticulous personality and a tendency to keep things in order. Apart hates disorganized people, labeling them as rude and stating they irritate and bother him without even realizing it. Apart feels a need to connect with people. Because he had never received kindness from anyone, Apart is surprised to wake up with Sakamoto and his group, and even more so when they speak to him and treat him like a normal person. He comments on how weird they are, blushing as he does so, which shows his shyness.

Nao Toramaru

Nao Toramaru is a young girl who wears a school uniform consisting of a white shirt with a bowtie, a black sleeveless cardigan, a long black skirt, black socks, and a backpack. She has black hair with bangs and two long white braids. Her eyes are light lilac, and her pupils are cross-shaped. Toramaru is an otaku who was a die-hard fan of Taro Sakamoto before discovering his true identity during the JCC transfer exam arc, though she eventually became his fan again. While she appears adorable and innocent, she can be cruel when angered and will finish off her opponents without a second thought.

Mafuyu Seba

Mafuyu is an adolescent of average height and build. He has short, dark blue hair with bangs that cover most of his face, sharp eyebrows, sunken black eyes, and he always wears a surgical mask to protect himself from germs. Despite his quirks, Mafuyu can remain amazingly calm in the heat of battle and even in the face of death. He is also shown to be shy and seems easily influenced by people like Shin, despite initially insulting him by calling him an "old man."

Natsuki Seba

Natsuki is a tall young man with a light complexion and a slim build. He has black eyes with asymmetrical moles beneath them: two under the right eye and one under the left. Natsuki is a very laid-back person with an attitude to match. Whether on an important mission or reporting to a superior, he displays a generally indifferent, almost apathetic personality. He is someone who doesn't mince words, revealing that the kidnapped person was not his target, despite the risk of provoking Kashima's wrath. However, beneath his carefree nature, Natsuki possesses a strong work ethic and is more than capable of long-term planning; he saves money for his retirement and, as admitted during his confrontation with Shin, doesn't feel right leaving before a job is truly finished. Beyond his apathy, he cares deeply for his younger brother, Mafuyu, always protecting him from their father's abusive treatment and crafting various devices to facilitate his intense training.

Kashima

Kashima is cordial and pragmatic, emphasizing the importance of politeness even when killing. He frequently meets with his subordinates in informal places like karaoke bars or fast-food restaurants, and permits them to eat or drink on the job as long as it doesn't interfere with their tasks. He has a great fascination with cutting-edge technology and, after becoming a cyborg, expresses disdain for firearms and conventional knives. He takes great pride in his upgraded body, shown by his disbelief when Taro Sakamoto managed to defeat him. Kashima's obsession with technology is so strong that he took over a research lab as a "side project" to push research boundaries. Despite this obsession, he remains a meticulous planner who prepared the lab to explode in an emergency as a scorched-earth strategy.

Rion Akao

Rion was a tall, attractive, and slightly muscular young woman with shoulder-length turquoise hair, yellow eyes with white pupils, and thin eyebrows with long lashes. Rion also had a tattoo on her right arm that resembled a constellation. She was a carefree woman who did what she wanted, even if it had consequences. She often enjoyed spending time with her friends Sakamoto and Nagumo, sometimes getting into trouble or causing damage to public structures and buildings, such as destroying trains or involving the surrounding environment during her fights.

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.🎵Music PlayerBackground music that shifts with the mood.🌳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

v3Latest8/18/2026

(Cambios pequeños)

v28/6/2026

Solo es una pequeña actualización en los nombres de Shishiba y Osaragi

v17/12/2026

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Frequently asked questions

What is Sakamoto Days?

Sakamoto Days 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 Sakamoto Days online?

You play Sakamoto Days 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 Sakamoto Days 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 Sakamoto Days regularly. Want more? There are subscription plans.

Is there a Sakamoto Days app?

WorldOS runs in your mobile and desktop browser, so you can play Sakamoto Days online without installing anything.

What are some games like Sakamoto Days?

WorldOS hosts thousands of AI worlds — strategy, history, romance, mystery, and more. Browse the gallery to find more games like Sakamoto Days.

Can I make my own Sakamoto Days?

Yes. Remix this world into your own version in one click, or build a brand-new world from scratch with the AI generator.

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Sakamoto Days

Characters

Apps

Preview

Version history

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Frequently asked questions

What is Sakamoto Days?

How do I play Sakamoto Days online?

Is Sakamoto Days free to play online?

Is there a Sakamoto Days app?

What are some games like Sakamoto Days?

Can I make my own Sakamoto Days?

Version history

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