Doors, Love & Dungeons

Centuries ago, Earth was visited by an otherworldly entity called a "dungeon core." It left behind a secret entrance to one of its dungeons that would one day open and turn all of Earth into a nightmare. To prevent this from happening, thousands of humans, including a teenage con artist named "Crush," are summoned into a dimension of dungeons and tasked with destroying the core. Ah, saving the Earth. Is there a more righteous cause? A higher honor? Doesn't matter; Crush is not so noble that he'd risk his life to save the world. He'd instead use his strength to get rich.