O'Leary writes contemporary romantic fiction, often employing unconventional premises and dual narrative perspectives. The Flatshare, her debut, follows two people sharing a flat and bed on alternating shifts—a constraint that forces character development and emotional intimacy. Her subsequent novels maintain her focus on character-driven narratives exploring relationships, personal growth, and life's unexpected turns. O'Leary's approach emphasises emotional complexity and realistic dialogue. Readers seeking contemporary romance with distinctive concepts, strong character work, and emotional authenticity appreciate her novels.