Xavier is one of the two protagonists and point-of-view characters in the novel. Though he is the only son of Colombia’s wealthiest man, Alberto Castillo, and is the heir to Alberto’s fortune and company, the Castillo Group, Xavier exudes a laid-back attitude and remains steadfast in his ironic “commitment to non-commitment” (5). He is the “picture of insouciance” and is widely known for avoiding his responsibilities in favor of attending a good party (3). Though Sloane believes that Xavier is intelligent, she also believes that he applies his mind to all the wrong things. She considers Xavier to be her client with the most wasted potential.

Xavier finds pleasure in irritating Sloane; by stoking her anger, he is able to see beyond her “ice-queen façade […] long enough to reveal a glimpse of the real person underneath” (9). For this reason, he devotes himself to forcing Sloane out of her carefully crafted box, using tactics such as dragging her on vacations, teaching her how to dance, or getting her to confront her fear of attachment.

On a personal level, Xavier has trouble with Overcoming the Fear of Failure—an issue that stems from a childhood tragedy in which his mother died in a house fire that he accidentally started.