One day, while Saeki Maho visits her favorite hangout spot, her local home center, a sudden Earthquake knocks her unconscious. When she awakens, she discovers she and the entire home center have been transported to another world at the bottom of Melquodia Dungeon, home to the fiercest monsters imaginable. Joined by a misfortunate adventurer named Fiona, Maho needs to find a way out of this dungeon, but luckily, she has everything she could need in one convenient place...