Cupid's Bow

A Cupid's Bow refers to a sigil inscribed in a cupid's palm. It appears as a tattoo in the form of a bow and an arrow. This sigil enables cupids to catalyze emotions and relationship among humans. It is revealed upon the will of the cupid. Removing this bow, or the image of the bow, completes the second trial to expel angels from Heaven. This was achieved by Castiel when he carved out the bow from a cupid who willingly gave it up.