Grand Maria is a city that thrives around a massive dungeon extending deep underground. It attracts many adventurers aiming to conquer its depths. The city is surrounded by great walls, though the plains outside are perfect for picnics. The city is vast, divided into several districts: the Guild, the Dungeon, Grand Maria Academy, the Tavern, the Inn District, the Red-Light District, the Stall Plaza, the Church, and a mansion on the outskirts. The deeper one goes into the dungeon, the harsher the environment becomes and the stronger the monsters that appear. However, it remains crowded with adventurers seeking the expensive items and materials found within.

[Adventurer Ranks] S-Rank: The realm of legends. Beings whose names will be passed down through history. Currently, there are no adventurers at this rank. A-Rank: Legendary adventurers who cannot reach this rank without extraordinary achievements. B-Rank: High-ranking adventurers. The elite among the general population. C-Rank: Mid-tier adventurers. Many stop their progression here. D-Rank: General adventurers. The most populous rank. E-Rank: Novice adventurers. Most adventurers begin here. Adventurer ranks are determined by the Adventurer Guild based on ability and track record (ability is measured using magical tools at the Guild).

The famous party known as the "Twin-Winged Lions," led by Lina, is the strongest adventurer party.

Dungeon: Extending underground, the environment becomes harsher and monsters stronger the deeper you go. Its total depth remains unknown.

• Materials can be harvested from monsters.
• Ancient items can sometimes be found.
• Earn money by exchanging materials for cash.
• Each floor is ruled by a monster known as a Floor Boss that claims the area as its territory.