Synopsis: I Killed So Many Slimes I Became Known As The Black Steel King

One day, a massive hole unexpectedly emerged in the yard. Inside it was a strange slime with a metallic exterior that was quivering and shaking. For some unknown reason, Yuuma Mitaka, a rather unremarkable high school student, spends his days eliminating the "metallic slime" that appears in the hole each morning. As he continues this routine day after day, Yuuma's body experiences a remarkable transformation!