If you loved the surreal landscapes and the sense of dislocation as Titus wanders through a strange, unfamiliar world in Titus Alone, you'll be beguiled by The Third Policeman. O'Brien's novel leads you through an absurd, hallucinatory countryside where logic is twisted and reality is constantly shifting, much like the odd, alienating city Titus explores. The novel's blend of dark humor, bizarre imagery, and existential confusion echoes the unique worldbuilding and tone of Peake's work.

If you were drawn to the philosophical undertones and questions of identity and existence that shadow Titus's journey outside Gormenghast, The Invention of Morel will intrigue you. Casares crafts a mysterious, mind-bending narrative about a fugitive who discovers a strange island and an impossible love tied to the nature of reality. Like Titus Alone, the novel is dense with allegory and prompts reflection on perception, memory, and the self.

If you appreciated the psychological complexity of Titus as he grapples with alienation and sanity in a surreal, mechanized city, Lanark offers a similarly compelling protagonist. Lanark, lost between two worlds—one resembling Glasgow, the other a nightmarish dystopia—struggles with identity, mental health, and belonging. Gray's novel is celebrated for its deep psychological insight and intricate exploration of a character's inner life against a backdrop as bizarre as Peake's.

If you found Titus's ambiguous morality and uncertain motives fascinating as he's cast adrift in a confusing new world, you'll be riveted by A Scanner Darkly. Bob Arctor, an undercover narcotics agent, is torn between his identities, unsure of who he is or whom to trust. The novel explores personal disintegration and moral gray areas with the same sense of paranoia and existential uncertainty that colors Titus Alone.

If you enjoyed the absurd logic and sly wit that runs through Titus’s encounters with the eccentric denizens of the city, Alice's Adventures in Wonderland is a classic choice. Carroll’s playful, nonsensical humor and inventive, dreamlike settings mirror the offbeat, darkly comic tone that makes Titus Alone so distinctive.