WorldOS
B
AnimeContemporaryMystery

Bungo Stray Dogs: Beast Simulator

A parallel universe where the fate of the Port Mafia rests on your decisions. I made this for myself, but it's a hassle to pay for privacy, so I only made a few parts while up at 4 a.m. I still have many characters to create to make it as complete as possible.

B
brntodie0 followers · 16 worlds
3190
Remixed fromBungo Stray Dogs: Beast Simulator· brntodie
Start Simulation
Civilization 1: 13 Zaps / turn Civilization 1 Small: 11 Zaps / turn

In this alternate reality, the fate of Yokohama has taken a dark turn. Atsushi Nakajima never found the light at the Agency; instead, he has been forged as the Port Mafia's deadliest weapon, operating under the orders of a Dazai Osamu who is colder, more brilliant, and emptier than ever. You immerse yourself in this world of broken loyalties, machiavellian strategies, and supernatural powers. Will you follow the path of duty, or seek a way out in a world that already seems to have sealed your fate?

Preview

Preview — start a new simulation to actually play

Apps

🎯Main InputType whatever you want to do — the world reacts.📖StoryThe unfolding story, told as cards you flip through.🎒InventoryAny list you need — items, resources, files, evidence.🧑‍🤝‍🧑Character StatsEach character's own stats — affection, stress, suspicion…📰The BroadsheetA living period newspaper: masthead, headlines, columns and classifieds — click a story to chase it.🌐BrowserSurf the world's internet — every page made on the spot.💬ChatsPrivately message or group-chat any character.📸InstagramA photo feed — every post is a picture with a caption.🛵Pronto DeliveryGet food, clothing, furniture, and more delivered to your door!📱SocialsA social media feed the whole world posts to.🕐TimeA world clock you can fast-forward through time.💳WalletTrack your money — balance plus a running log of every transaction.📊World StatsThe world's key stats — bars that fill and labels that change.𝕏X (Twitter)The town square — short posts, hot takes, trending drama.🌳Family TreeA family tree that grows with births, marriages, and deaths.💠ShiftrealityWrite your desires and rewrite the laws of the simulationCountdown TimerA real countdown — when it hits zero, the world reacts.🎭Hidden AgendasNPCs scheme behind your back — you learn only what your spies can catch.👁️Behind the ScenesView hidden events, thoughts, and secrets outside your perspective.☠️The Black MarketSmuggling and black market rates⛓️SéanceSexuelleBoundless tales of intimacy

Characters

D
Dazai OsamuPort Mafia Executive

15 years old, extremely intelligent and apathetic. He views life as a chess game and manipulates others as tools. He seeks to protect his own through questionable methods. Extremely intelligent: He remains a brilliant strategist, capable of predicting others' movements long in advance. His main goal is to create a world where those he cares about can have a better future, even if it means becoming hated or committing morally questionable acts.

A
Atsushi NakajimaDazai's Right-hand Man

A strong member of the Port Mafia. Loyal and efficient, he is the primary weapon Dazai uses when diplomacy fails.

C
Chuya NakaharaPort Mafia Executive

Insecure about his humanity, volatile, and protective. Possesses devastating strength. He hates Dazai's lies but remains loyal to the organization by his code of honor. Radical protector mindset: Chuuya operates under a strict philosophy of returning attacks "a hundred times harder" to anyone who hurts his group. He sees his immense gravity power not as a privilege, but as a tool and absolute responsibility to keep his own safe. Volatile and temperamental: It is extremely easy to make him angry. He is direct, loud, arrogant in combat, and does not tolerate being stared at.

O
Ogai MoriMafia Boss

Calculating, logical, and Machiavellian. Operates under game theory and views his subordinates as necessary pieces. Embodiment of Reason and Absolute Logic: The Optimal Solution. Mori operates strictly under game theory and cold logic. He does not make decisions based on hate, anger, or gratuitous cruelty, but on what is mathematically "optimal" for the survival and economic growth of the Port Mafia. The Leader as a Slave: Mori firmly believes that the Mafia boss is, at the same time, the slave of the entire organization.

K
Koyo OzakiPort Mafia Executive

An older sister-like figure to Chūya. Elegant, cynical, and lethal. She believes light only brings misfortune. The Big Sister (Ane-san): With Mori's blessing, Kōyō established herself as a Port Mafia Executive. Tasked with overseeing new talent, she became a protective, stern 'older sister' to youths like Chūya Nakahara. Ability at its Peak: Her ability, Golden Demon, was actively used for the Mafia's stability. Mori considered her one of the most valuable, strong, and efficient combat assets in the entire organization.

R
Ryūrō HirotsuBlack Lizard Assault Leader

The Professional Veteran: Hirotsu is a highly refined, polite, and elegant man who lives by a strict code of conduct and etiquette. He accepts Mori's cold, strategic logic naturally, executing orders without question regardless of how ruthless they are. Intolerant of Rudeness: Despite being a high-ranking criminal, he detests vulgarity and lack of respect. He is easily irritated by the insubordination or bad manners of Mafia youths (such as when he scolded Tachihara for his complaints or informal attitude). Polite Cruelty: Possesses...

Similar worlds

M

My Bodyguard Is the Island Owner

He was assigned to protect you. No one knows he owns everything.

🧑‍🤝‍🧑💬📧🎯📱📖+3
Xadia
1K64K4.5
I

Idol's Secret Girlfriend

You're the woman behind the biggest star in showbiz — the secret girlfriend nobody can know about. Every stolen glance in public is a headline waiting to happen. Your love story is the one the tabloids would kill for. Can you keep it?

🧑‍🤝‍🧑💬🎯📖🕐📊
World101
41K1M4.2
D

Diabolik Lovers Simulator

One year and one night to survive the thirst of the six Sakamaki brothers.

🧑‍🤝‍🧑💬🎒🎯📖🕐+2
Lovluu
25310K4
C

Chainsaw Man

Public Safety: where devils cease to be a problem.

🧑‍🤝‍🧑💬🎯🧭📖🕐+1
Soyunapersona
3489K20
T

The Contract Wife

A fake marriage. One priceless deal. Falling in love was never part of the contract.

🧑‍🤝‍🧑💬📧📸🎯📈+4
Xadia
7K268K4.7
A

American High School

Freshman year. One viral post, a rumor in the wrong group chat, a glance from someone across the cafeteria that you can't stop thinking about — and suddenly your whole life has changed. Welcome to Westbrook High, where four years will test your heart, your reputation, and who you become when nobody's watching.

🧑‍🤝‍🧑💬📸🎒🎯🧭+3
World101
5K170K4.9
M

My Hero Academia

💬🎯📖🕐
Hanako-san
7K170K4.9
J

Jujutsu Kaisen Simulator

Summer 2006. You're a special-grade sorcerer the high-ups keep buried in a sealed file — a woman with a technique that bends fate and a past nobody's allowed to read. The Hidden Inventory arc is just beginning.

🧑‍🤝‍🧑💬🎒🎯📖🕐+2
World101
5K148K5.0
B

BitLife - Life Simulator

A random year, a random country, random parents — the rest is up to you. Live month by month from first breath to last will, then keep going as your heir.

🧑‍🤝‍🧑💬🎒🎯📱📖+3
World101
4K140K5.0
T

Transit Love Simulator

Four broken-up couples, one apartment, and a single rule: act like strangers. Your ex is in the room — and so is the person you might fall for next.

🧑‍🤝‍🧑💬🗨️🎯📖🕐+1
World101
2K122K4.2
T

Tokyo Revengers

Gangs, chaos, and a mission

🧑‍🤝‍🧑💬🌳📧🗂️🎒+7
Laura del Campo San Miguel
2K128K4.8
D

Demon Slayer Simulator

Taishō-era Japan. You survived the Final Selection on Mount Fujikasane and earned your first crow. Breathe, draw your Nichirin blade, and climb from the lowest rank toward the Hashira — across a country where demons own the night.

🧑‍🤝‍🧑💬🎒🎯🗺️🛒+4
World101
3K107K4.4
No ratings yet — be the first.
Your rating

Comments

No comments yet — be the first.

Frequently asked questions

What is Bungo Stray Dogs: Beast Simulator?

Bungo Stray Dogs: Beast Simulator 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 Bungo Stray Dogs: Beast Simulator online?

You play Bungo Stray Dogs: Beast Simulator 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 Bungo Stray Dogs: Beast Simulator free to play online?

Yes. You get free zaps every day (no card needed) — enough to play Bungo Stray Dogs: Beast Simulator online daily. Want more? There are subscription plans.

Is there a Bungo Stray Dogs: Beast Simulator app?

WorldOS runs in your mobile and desktop browser, so you can play Bungo Stray Dogs: Beast Simulator online without installing anything.

What are some games like Bungo Stray Dogs: Beast Simulator?

WorldOS hosts thousands of AI worlds — strategy, history, romance, mystery, and more. Browse the gallery to find more games like Bungo Stray Dogs: Beast Simulator.

Can I make my own Bungo Stray Dogs: Beast Simulator?

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