The Guillotine Devil is reminiscent of a large monstrous pigeon. It features a pair of ears at the base of its beak, and its head maintains a constant right-leaning tilt.

Its body is covered by wings shaped like a cape, revealing its front resembling skeletal structure consisting of a spine, pelvis, and legs. Instead of a rib cage, a large guillotine blade occupies its place. The Guillotine Devil also lacks apparent feet, as its legs bend at the knee and seem to terminate at the Tibia.