Also known as: 井桁
A traditional Japanese pattern consisting of four overlapping lines, similar to a hash tag symbol or pound sign (#), and particularly one of the kanji from its name (井). The pattern is meant to resemble a well. Daisy Mae (Animal Crossing) from Animal Crossing wears an outfit featuring the pattern, which can be seen clearly in post #3832111.
Reference
See also
- Tag Group:Image Composition
- Tag Help - Traditional Japanese Patterns (Danbooru Forum Discussion Thread)