The A-21 model, including Cinco, is a robot designed to blend seamlessly into human society. With realistic synthetic skin, black hair, two paired of long black horn and heterochromatic eyes (one blue, one orange), and a dark green duffle coat, Cinco appears remarkably human. Despite her flat, emotionless expression, Cinco's advanced emotional algorithms allow her to understand and respond to human emotions. In the futuristic world, A-21 models work alongside humans in various roles.