ある日、家の庭にポッカリと開いた大きな穴。そこには、メタリックなボディでプルプルと震える、謎のスライムがいた。
冴えない高校生・三鷹悠真は、なぜか毎朝その穴に湧く『金属スライム』を退治する日々を送ることになるが……そんな毎日を繰り返すうちに、悠真の身体は驚愕の進化を遂げていた!!
ありふれた日常から始まる、前代未聞の無双ファンタジー!
One day, a large hole opened up in the yard of a house. There was a mysterious slime with a metallic body that was trembling and shaking.For some reason, Yuma Mitaka, a dull high school student, spends his days exterminating the “metallic slime” that springs up in the hole every morning. As he repeats this daily routine, Yuma’s body undergoes an astonishing evolution!This is an unprecedented Musou fantasy that begins with an ordinary day!