One of the themes of the oriental world is the division of internal versus external, the hard versus soft, the balance of yin versus yang. This appears in the the droid manufacturing processes of the entire world, but most prominently in the East. The West divides it's droids into two different classes, rigid shelled autons and softer human simulacra like the sex droids. The only other types of machines are those that emulate the biomechanics of insects, or the ultra-utilitarian purpose designed machiens. In the East, the rigid shelled droid was poorly received by the general populace. Such machines were hard, their purpose was war, regardless of what role they were serving. There simply wasn't a way to style a machine with a rigid exoskeleton to be anything but a warrior. Thus the government of China initiated the Xiaoxang Project.
The Xiaoxang Project
The purpose of the Xiaoxang project was to create an 'internal' or soft style droid that would serve the same roles that the hard carapaced auton served in the West. The project was rather expensive as Western autons looked human, but their internal structure was simple, mimicking the function of insect physiology. Inside their arms and legs there were no bones, and the function of their limbs was based on synthetic muscles and servos pushing and pulling against joints and their carapace. The Xiaoxang droid would emulate the biomechanics of a human being, with internal bones and supports. The mechanics remained similar, but no longer were afforded the luxury of an outer shell.
The end robots created with bizarre mockeries of humanity. They resembled burlap men, hence the name they ended up with, the Mabu-Ren. The internal chassis of metal, ceramic, and plastic were wrapped in layers of synthetic materials. The worst part of the mabu-ren were their faces. Instead of a human face, they viewed the word through a fixed plate, unmoving sensors, the rest of the head covered in a tight fitting cowl of synthetic material.
The project almost failed, despite the money and time spent on it. The answer was found in a simple place, a mask. The mabu-ren are most often deployed in human assistance roles, and it was simple enough to costume them up. Their bodies were easy to conceal in human clothing. Given their use in menial tasks, the appearance of humanoids in workers garb, or clean up suits, is easy to accept. Their heads are covered by workers masks, or by workers hoods.
The Decadence of the West
There are many salient points in the conflict of culture between the ACPS and the rest of the world. The two most prominent salients are the tradition and history of China, and communistic pragmatism. To the the ACPS, the West's parade of clones, genetic augmentations, pillow droids and puppets, and the endless flow of consumer robotics. The mabu-ren are all property of the state. They are the new terra cotta army, answering to the leaders of the Asian Co-Prosperity Sphere.
Possession of a mabu-ren is a sign of great honor and respect. Only ministers of the state, important officials, and those who have demonstrated their loyalty to the emperor are deemed worthy.
Background Color - one of the striking differences between the western nations and the ACPS is the presence and role of robotics. In the west, robots are seen as common property, and can be found almost everywhere doing almost everything. In the east, the mabu-ren are only seen in the background. These machines are the eyes and hands of the emperor, and to disturb them is to disturb the emperor. Thus, where machines are used as sex dolls and demolition derby fodder in the Federation and Coalition, they are treated with great respect in the East.
The Virus - a rogue AI has created a virus to corrupt the code of the mabu-ren. This can be mundane data mining and surveillance, but could also be much more insidious, leading the machines to commit murder or other acts of mayhem, undermining the authority of the Emperor and showing the weakness of his machinery.
Additional Ideas (1)
The servant robots of Ergo-Proxy are an excellent example of the mabu-ren style of robotics, with a few fixed panels, but largely supple bodies and while demonstrate the traditional stronger than humans trope, are not necessarily any more durable or tougher than the average human.
The Soldiers of the Foot
The classic TMNT cartoon turned the soldiers of the Foot Clan into purple clad robots, so that their destruction wasn't considered violent by the censors. These robots served menially, and went into battle silently, and proved little threat except in great numbers.