Joker operates as a genetically engineered cyborg operative designed for law enforcement, possessing shape-shifting abilities and gender fluidity enabled by adaptive DNA absorption. Commissioned by a clandestine Special Police Task Force, Joker wields autonomous authority as cop, judge, and executioner, patrolling a fractured dystopian metropolis. Physical adaptations align with mission parameters: a combat-optimized male form prioritizes tactical brutality and augmented strength, while a female-presenting identity employs traditionally feminine traits, utilizing charm and emotional intelligence for undercover operations and romantic entanglements.

Originating from Dr. Bayfarm’s experimental labs, Joker emerged as the "perfected" prototype alongside a rogue android counterpart, exhibiting unexpected compassion and emotional complexity absent in its unstable sibling. A partnership with human officer Rin anchors the narrative, blending duty with unresolved intimacy. Romantic tensions surface exclusively during Joker’s female manifestations, constrained by societal expectations that inhibit Rin’s reciprocation in male-presenting encounters.

Though equipped for strategic versatility, Joker’s operational capabilities prioritize physical confrontations over investigative applications, with metamorphosis primarily influencing interpersonal dynamics rather than tactical advantage. This duality underscores themes of performative identity within systemic violence, though narrative emphasis rests on kinetic action and charged relationships. Post-mission, Joker disengages from formal duty to investigate cryptic connections to Dr. Bayfarm’s legacy, concluding their arc with ambiguous independence.