It's just chocolate
An excuse made when people see any of your personal belongings covered with brown stains. This phrase is mostly used as a defense against the assumption that the stains derived from feces.
Guy: How do like my room babe.
Girl: It's nice. (Looks at bed sheets) Why are there brown stains all over your bed?
Guy: Uh... it's just chocolate.
Girl: It's nice. (Looks at bed sheets) Why are there brown stains all over your bed?
Guy: Uh... it's just chocolate.