Raoul de Chagny is a viscount and Christine Daaé's childhood friend. They first met when he was a young child when he went on vacation in Northern France. He meets up with her again after watching her performance at the former managers' retirement ceremony at the Palais Garnier. He reminds her that he is "the little boy who went into the sea to rescue your scarf," which provokes her laughter. At first, Christine refuses to recognize Raoul, in fear that the "Angel of Music" would return to heaven. However, they become engaged later. Unknowingly to them, Erik had been spying on them. On the day they were going to elope, Erik kidnaps her during a performance of Faust at the opera house. Raoul then, along with the mysterious man known as "The Persian", goes down into the cellars of the Opera in an attempt to rescue Christine. He and the Persian endure near-drowning and torture in a mirrored, super-heated chamber before Erik eventually relents due to Christine's willingness to sacrifice her happiness for torture, and has to be put to bed by Erik because the treatment has left him "limp as a rag."

In Gaston Leroux's novel, The Phantom of the Opera, Raoul is described as having a small, fair mustache, beautiful blue eyes, a complexion like a girl's, and an air of "just having left the women's apron-strings." His elder brother and former guardian, Comte Philippe de Chagny, is a man of the world who indulges in a dalliance with the Opera's prima ballerina, Sorelli, and is exasperated by his brother's attachment to "the little baggage" Christine. Philippe is later drowned by Erik when he goes looking for Raoul in the cellars of the Opera.

Raoul has been to sea, and plans to go on a suicidal polar expedition if Christine refuses to pledge herself to him. He is puzzled and sometimes angered by her allegiance to Erik, and thinks that she may be toying with his heart. He is the youngest member of his family, with an older brother (Philippe De Chagny) and two sisters already married. However, in the film adaptation of the Andrew Lloyd Webber musical he mentions his (still living) parents, who had passed away long before the events of the novel.

In many adaptations (such as the 1990 miniseries), Raoul's character is ommitted entirely in favor of a different love interest for Christine.