Unnamed background characters that are not part of an image's focus, usually to bring life to a scene and make spaces look less empty. They may be drawn at considerable distance from the viewer, or established as an insignificant part of the image.
Occasionally the background people can also be formed of relevant named characters, or named characters can be dispersed in an unnamed crowd as details. In this case they can be included in the character counters.
If there are large number of background people in the image, the tag crowd is applicable.
The opposite of people is solo. If you want to go even further, try no humans.
