Yūji Sano works at a company that is harsh on its employees. After bringing some overtime work back home, he gets a message on his computer: "You have been summoned to an alternate world." It is a game-like world, complete with status bars and skills. Yūji tames a slime monster and thus becomes a tamer. Then, he suddenly attains a second profession — sage — and awakens magical powers within himself. Yūji's alternate world adventure begins when he follows a slime, that seemingly weakest of all monsters. (from manga)