Final answer:
The phrase 'a veritable angel of mercy' describes a compassionate character in literature who provides help and comfort, and is not specific to a single character or work.
Step-by-step explanation:
The phrase 'a veritable angel of mercy' is often used to describe a character who is exceptionally compassionate and provides help or comfort to those in need. This expression is not tied to a specific literary work, as it can be used broadly in various contexts to highlight a character's kindness and benevolent nature. In literature, such characters often play crucial roles that drive the narrative forward, either by providing relief or support to protagonists, or by inspiring them to overcome adversity. These figures are frequently portrayed with a certain moral superiority or saintliness, making their actions pivotal to the resolution of conflicts or healing within a story.