A trend of the 2000', dollz and sprites are pixel art, in this cas they are virtual dolls of various size, their details are created pixel by pixel with a image editing software. Their interest is artistic and entertaining for their creators who are usually part of a pixel art community, and it can become a collection or decoration for the adopting people. One gold rule to follow when one wants to display a doll on their site: indicate where the dollz come from and who made it (it is not at all a free to use GIF).
When we stumbled upon a dollz related to Angel Sanctuary, we quickly opened a page on the subject and started to adopt ^^ and even created a few!
Rule reminder: dollz belong to their owner. If you want to adopt one, you must indicate proper author credit (name + email or website).