Robot Adept

Piers Anthony continues the saga of Mach, the brave and sensitive robot from Photon, and his alternate self, magical Bane from Phaze, as they fight to keep the loves they found and save their worlds from destruction.
Having discovered how to change places with their alter egos, Mach and Bane fall into forbidden love, but their delights are short-lived when bitter feuding erupts within and between the two frames. For Proton and Phaze are ripe with the seeds of revolution. As the only ones capable of communicating between the frames, Mach and Bane hold the power to link the two warring systems—or destroy them entirely! Hunted by the Contrary Citizens in Proton and forced into an uneasy alliance with their counterparts in Phaze, Mach and Bane and their lovers are caught in a web of intrigue for which they are ill prepared. Novices in politics and warfare, they must learn to play both political factions off each other, switching loyalties and identities at the blink of an eye, while racing against the clock to save the worlds they love from harm.