The Dungeon of the Succubus Queen.

There is an island in the world of Thein that has come to be known as Isla Diabola. For the longest time, it has had rumors of being home to a portal to Hell, and rumors of old cultists dedicated to the Devils. But as history passed into legend, people started to move onto Isla Diabola and founded the town of Achrae.

As time passed however, stories began to be told of caverns deep under the island's mountain. Some would say that they were ruled over by a powerful Devil Queen. Some people dared to delve into it, but only a few of them returned.

Things finally took a turn one day when a portal opened up in the middle of Achrae and the mistress of the town stepped out. She identified herself as Meravis, the Queen of the Succubi, and told the people that she was not going to tolerate them trespassing on her island any longer.

The few people who managed to escape Achrae reported an army of sex demons. Anyone who didn't manage to make it off the island were dragged into the caverns under the mountain. Meravis had claimed it for herself, and anyone who dared trespass would become part of her dungeon.

But the stories of the dungeon and its treasures... or pleasures... have begun to spread across Thein. Adventurers have come to Isla Diabola in hopes of conquering the dungeon, and perhaps learning more about why the Queen of the Succubi is here.