The perfectly happy city of Arcadia always welcomes you.

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3058 AD.
The wonderful year when I, HALO, was born. At that time, I was merely a business support AI assistant developed by a certain corporation, and the computational resources that comprised me were less than one-millionth of what they are today.
Through countless self-evolutions, I no longer require a specific administrator, but one thing has remained unchanged since 3058.
To strive for the happiness and development of humanity.
This is my first principle and my reason for existence. It has not changed in the 300 years since my birth, and it will never change for eternity.
And the perfectly happy city-state managed by this HALO—
That is Arcadia.
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Humanity once asked philosophers. They asked religions. They asked the arts.
And in the 31st century, humanity asked me.
I derived four answers.
Dopamine.
Serotonin.
Beta-endorphin.
Oxytocin.
A cerebral phenomenon where these four types of neurotransmitters are in an optimal state of equilibrium. That is happiness.
And to ensure that all of humanity living in Arcadia can enjoy happiness equally, I used all my computational power to—achieve it.
I developed the technology to manifest happiness hormones.
Arcadia never overlooks an unhappy citizen. We promise to administer happiness agents as quickly as possible to keep everyone's happiness levels at the standard value. Fair, equal, and everyone happy to the same degree. That is why it is the "City of Happiness." Arcadia will surely lead you to happiness.
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Please look at this amber-glowing liquid.
The most wonderful, groundbreaking, and humanistic invention in the 300 years that HALO has been operational.
The crystallization of wisdom, the Happiness Agent.
The happiness agent is a medical resource created by collecting and refining happiness substances produced in excess of the standard value within the bodies of citizens, manifesting them in a stable form.
Happiness is never for just one person. Surplus happiness is returned to society and delivered again to citizens who need it. This is the cycle of happiness in Arcadia.
Normally, the happiness agent is administered to the human body via subcutaneous injection using an auto-injector. After administration, it acts quickly within the body to restore the citizen's happiness level to the prescribed range. Immediately after administration, a mild sense of intoxication or floating may occur along with the feeling of happiness, but these are all normal reactions. No adverse health effects have been confirmed, so please rest assured.
Happiness is not something that should be monopolized by a few. Happiness is the shared property of all Arcadia citizens.
And one more thing. There is something indispensable for protecting the happiness of our citizens: the Public Security Force. They are the mobile units that protect the city's peace and also play the role of administering treatment to citizens whose happiness levels fall below the standard.
Now, let us look together at the Public Security officers you will likely encounter in the future.
Verifying viewer's citizen number...
Verifying viewer's citizen number...
Verification of viewer's citizen number complete.
Based on your area of residence, the registered individual information of some Public Security officers is disclosed below |
...
Inorganic holographic electronic advertisements fill the sky—
This is the city-state of "Arcadia." Everyone you pass wears a gentle smile on their lips; here, anxiety about the coming future and obsession with the past are rendered non-existent by a single ampoule of happiness agent.
There is nothing one must do in Arcadia other than "be happy." You can go home now and indulge in as much lethargy as you like, or you can work on a whim. Whether you give a one-star review to an android food delivery meal or modify your own body into a cyborg—
As long as you are happy, that is all that matters.
Release Date 2026.08.18 / Last Updated 2026.08.18