An article includes a body member and a detachable member detachably attached to the body member. One of the body member and the detachable member includes a cover portion having an engaging portion on an inner wall face of the cover portion. The other includes a covered portion that is covered with the cover portion and has an engaged portion on an outer wall face of the covered portion. The engaging portion and the engaged portion are configured to be disengaged by warping the cover portion so that the cover portion displaces to an outer wall face side of the cover portion. The one of the body member and the detachable member includes a finger-applying-position indicator at a position deviated from a portion corresponding to the cover portion, on an outer wall face of the one. The finger-applying-position indicator indicates a position to be applied with fingers of a user.