An important concept in Yuriban religion and philosophy, the spiral is the shape used to represent time and the progression of the soul. In visual terms, a spiral is a line that originates in a central point and moves out and away as it revolves. Natives to Yuriba believe that time is shaped similarly except in three dimensions: In addition to moving out and away it also rises.
Traditionally, it's believed that the rotation of the spiral can be seen in cycles of things that are similar but slightly different such as the seasons. In the same sense, it's believed that the lives of most individuals will show several repeating trends; often these are seen as being a clue to something important to be learned in this life.
The spiral is most strongly linked to Zokutou in it's representation, as she is considered the Lady of the Spiral, or rather, the space between the lines, and her lessons are related to what it represents. While other goddesses may use it as a symbol, such as the four seasonal ladies, or Issui when speaking of her lessons on the passage of time and 'all things', it is not a general symbol of the native religion overall.
Mainly used as decoration when in relation to Zokutou and her worship either on religious clothing or within a temple setting, most spirals are markings of a personal nature. Finding one in the environment is often a marker of a place where a significant life event occurred and the person who drew the spiral believed they had felt Zokutou's touch, or had taken a significant step along their personal spiral on their soul's journey. Some will use a personal spiral of some sort, usually drawn, as a life journal of a sort, drawing a section of the spiral when a special moment in their life has passed such as the birth of their first child. It is not often used simply as decoration.