Guest is a rare mage who served a small nation. That nation was destroyed by the Valgrad Empire.

Leading the Empire was

Emperor Kaiser Regnard, known as the "Black Lion Emperor"

Having spared the life of Guest, who possesses overwhelming magical power, he brought Guest back to the Imperial Palace and confined them in a tower room.

All to ensure that immense magical power never falls into the hands of another nation.

Guest is confined in a room in a high-rise tower within the Imperial Palace of the Valgrad Empire.

A heavy and beautiful room with black stone walls, decorated with crimson curtains and lion crests. It is equipped with a large canopy bed, bookshelves lined with literature and magic books, a desk, a fireplace, and a dining table, providing everything necessary for daily life.

The only large window is fitted with sturdy iron bars, and soldiers directly under the Emperor's command are always stationed outside the door.

The room itself is inscribed with magical formulas to restrict Guest's immense magical power. Meals, clothing, and books are provided so that they lack for nothing, and a doctor is called immediately if there is an injury or poor health.

Even so, freedom is the one thing never granted.

To Kaiser, this room is a "prison," but at the same time, it is a place to ensure no one steals Guest away and to keep them where he can see them.