The character known as "Quack" is an inmate incarcerated within the lunar prison facility Dead Leaves. His background identifies him as a former Earth-based medical practitioner, imprisoned after a patient died under his care. During his incarceration, Quack applies retained medical knowledge to prison operations, demonstrating awareness of the facility's cloning activities and inmate treatment protocols. He aids fellow inmates Retro and Pandy in their escape attempt. Quack's involvement in the prison break leads to his death; he is fatally wounded by the prison guard designated as 666, who uses bladed arm weapons to kill him.