The summer heat showed no sign of fading.

Outside, the sky remained cloudless.

The air shimmered with the warmth of another tropical afternoon, and laundry dried almost as soon as it was hung.

There was no rain.

No wind.

Only brilliant sunlight and the reminder to stay hydrated while avoiding the strongest ultraviolet rays.

After completing his daily routine in Moo66, Usinomics stepped once again through the ocean gate.

As an official marine surveyor, today’s assignment was the same as yesterday.

Removing mysterious pollutants from the underwater ecosystem.

The work had become familiar.

Steady.

Peaceful.

When the cleanup was finally complete, the sea transformed from a workplace into an endless field of discovery.

Seaweed could be harvested.

Rare marine life drifted through the currents.

Ancient ruins waited silently beneath the waves.

Curiosity pulled Usinomics farther than usual.

He swam beyond the regular survey zone and entered waters few residents ever visited.

Then…

Something appeared.

A silver cat lay peacefully asleep before an enormous stone gate.

Its long, luxurious fur flowed gently with the underwater current like the coat of a Persian cat.

Only its elegant fish tail revealed that it belonged to the sea.

Perhaps fins were hidden beneath its soft coat.

From a distance, however, it looked almost entirely like an ordinary sleeping cat.

Without opening its eyes, the creature simply continued its nap.

Beyond it stood the entrance to an ancient civilization.

The Undersea Empire.

Usinomics slowly passed through the massive gate.

Surprisingly…

No passport was required.

No guards questioned him.

The city welcomed every peaceful traveler.

Towering stone buildings stretched across the ocean floor.

Coral-covered arches connected forgotten streets.

Soft blue light drifted through the water like floating stars.

It felt less like ruins…

…and more like a kingdom that had simply chosen to live beneath the sea.

One enormous structure immediately caught his attention.

An ancient clothing store.

Its weathered stone sign still remained.

Usinomics quietly read it aloud.

He smiled.

The familiar sound of the name made him chuckle to himself.

He never entered the building.

Instead, he remembered an old rumor.

Long ago, someone had spoken of the store’s representative—

A graceful man whose beauty resembled the brilliant feathers of a peacock.

Whether the story was true…

No one seemed to know.

As Usinomics continued through the city, another unexpected sight appeared.

A young man glanced toward him with a warm smile before swimming away.

Beside him floated a companion unlike any creature Usinomics had ever seen.

Its translucent body shimmered like polished crystal candy.

The soft light of the ocean passed through its smooth skin, making it glow from within.

Without saying a word…

The two simply held hands and disappeared together into the blue distance.

Usinomics quietly watched them leave.

No questions.

No interruption.

Only silent curiosity.

Who had built this magnificent civilization?

These structures were far too precise to have been carved by ocean currents.

They were not natural caves.

Nor ordinary rock formations.

Every archway…

Every staircase…

Every tower…

Spoke of intelligent hands.

Perhaps long ago, a catastrophic flood had swallowed an ancient island.

Perhaps an entire civilization had simply continued its history beneath the sea.

The truth had been lost to time.

Usinomics looked once more toward the endless city.

There would be time for answers another day.

For now…

Duty came first.

He quietly returned to the survey area, completed the remaining pollution cleanup, and finally made his way back through the ocean gate.

Far behind him…

The Undersea Empire continued its silent existence beneath the endless sea.

Waiting patiently…

For the day its forgotten history would finally be told.

He discovered the Undersea Empire.

He passed through the enormous stone gate.

A mysterious sign caught his eye.

AOZAMA Clothing.