There's a Monster Behind Me

The scary man-eating monster in the alley. A strange musician who crawls into your home in the middle of the night. There are also potions that grant extraordinary powers. The endless strange events happening in each room are constantly refreshing my knowledge. After so many experiences, is it the one that has always been by my side? A mysterious black monster that has been stalking me for a long time. I'll call it "chocolate" for now