On the continent of Astraea, a man drops from the sky, retaining no memories save for his name, Yuuki. An elf called Kokkoro discovers him, presenting herself as his guide through the world they are set to explore. Under Kokkoro's direction, Yuuki learns the mechanics of this world, ranging from fighting monsters to managing currency. To secure funds for their travels, Yuuki and Kokkoro choose to visit a local guild association and take on a straightforward quest. During this mission, they encounter Pecorine, a battle-skilled girl who is somewhat gluttonous yet charming. The following day, they also meet Karyl, a cat girl who specializes in magic. Eventually, a bond of friendship and camaraderie develops among them, leading the quartet to establish their own guild. As they pursue further adventures, they explore the world, encounter new individuals, and may perhaps reveal the secrets behind Yuuki's lost memories.