Harry Haller is the main character in Hermann Hesse's novel, "Steppenwolf." He is a middle-aged intellectual who struggles with his identity and the conflict between his human and wolf-like instincts. Haller feels alienated from society and grapples with feelings of despair and loneliness. Throughout the story, Haller embarks on a journey of self-discovery, exploring themes of duality and the search for meaning. He encounters various characters, including Hermine and Pablo, who help him confront his inner conflicts and ultimately seek a balance between his contrasting natures.