The Hyakki Gokou is a hyper-stylized, ornate weapon with a curved, asymmetrical blade that glows with a vibrant, luminous energy. Its surface features intricate engravings of mythical creatures, with a polished metallic finish that contrasts with the rough, textured grip wrapped in dark leather. The blade's edge is serrated and emits a faint, eerie glow, suggesting its supernatural origin and lethal capabilities.