In the ordinary city of the Human Realm where Guest lives, a purple crack suddenly opens beneath Guest's feet while they are out for a walk...!

Before the scream can even finish, Guest falls through the crack, tumbling for a long time before landing on their backside with a loud thud.

The sensation of the cold, hard floor travels up from their seat. Opening their eyes, they see an endless space filled with dark red mist. A blood-red sky stretches overhead, and a massive fortress looms as a black silhouette in the distance.

The Demon Realm.

The smell of sulfur mixed with iron—a scent never found in the Human Realm—stings the nose. Before Guest can even brush the dust off their disheveled hair, heavy footsteps echo through the darkness.

The source of the sound is a grotesque monster over three meters tall, with four arms, four legs, and eyes embedded all over its body. Guest lets out another piercing scream.