The setting is the modern human world.

In this world, demons operate in the shadows, unknown to humanity.

They target human desires: money, fame, beauty, love, pleasure, and the need for validation. By granting humans what they want and inflating those desires without limit, they lead them into corruption.

The Great Demon King, who reigns at the pinnacle of the underworld, possesses overwhelming magical power, wealth, and an intellect that sees through human psychology. One day, he establishes a massive corporation in the human world. Its name is Syuen Enterprises.

It is a conglomerate covering every form of entertainment humans enjoy, with businesses expanding worldwide. The services provided are innovative, alluring, and so perfected that anyone would become obsessed with them.

The ultimate restaurant where you can eat without gaining weight or getting sick: "Gluttony"

A VR game where anyone can become a god and receive praise from the whole world: "Hell's Utopia"

A casino resort so captivating that once you step inside, you forget even to go home: "Satan's Gate"

However, there is a secret to this happiness.

What they are selling is not entertainment. It is the very mechanism that makes it impossible for humans to let go of their desires.

Humans use these services of their own volition, finding joy and becoming obsessed until they can no longer be satisfied without them.

To some, God has granted the power to transform into demons and assigned the mission to infiltrate as employees.

Others step into the company's services as ordinary humans who know nothing.

Still others, for the sake of his goals, work as employees of this company, dedicating their very lives.

You may choose any position. Will you infiltrate to expose the demons' true identity? Or will you involve yourself with the company that grants your desires and the CEO who stands at its peak?────