Non-material beings or entities can be characterized by their qi. In fact I only became aware that such things really existed back in 1983 in Taiwan, when I first felt the qi of one of them in a Buddhist temple, and investigated more closely.

          Examples of non-material beings are angels, those which have responsibility for seeing to the welfare of certain geographic locations (spiritus loci) or (tu di shen) [as they are called in China]), those which have responsibility for looking after trees (devas), those whose responsibilities lie in the air (sylphs), those whose responsibilities lie in the water (undines), those who are associate with fire (salamanders) and the elementals which often have responsibility for specific plant (or other) organisms.

          The qi of the nymphs, sylphs, and devas which I have observed has always been quite positive. There are some beings whose presence is such that one innately is led to show them great respect: the qi of these entities is extremely positive, and it is to this group that what are often termed angels belong.
          Sylphs will sometimes clothe themselves in wispy clouds, making their outlines visible to the physical eye. But not all such wispy clouds contain sylphs.

          Though I have not given names to any particular classes of sha beings, such things do exist, and seem to be quite as numerous as sheng beings.