In our core, we are creative beings who are always looking for new ways to express the complex web of feelings and thoughts that lives within us.
In order to express themselves creatively, some people write down their ideas and thoughts, others construct physical things, while yet others work in the visual arts. What important is the act of expression, not the medium, and that others are able to see and understand it.
This is not an original idea. For eons, people have been molding and sculpting, putting their creative mark on almost everything we come across, from buildings and food to clothing and the careful layout of towns.
So, it's not surprising that many people choose to turn their own skin into a living painting.