But, unlike all the other genres covered in this column, crabcore isn't defined by sonics or BPMs or lyrical content, or tied to a geographic location. Crabcore is defined by the body contortions of the band's guitarists when they perform.
Source: wiktionary
In photos that seem straight out of an American Apparel billboard, a young woman poses in the T-shirt, which asks, “What kind of music do u listen 2?” and offers, in a matrix of small type, more than 200 underground musical styles, both real (shoegaze, crab-core) and fake (Sufjan-house, crab-gaze).
Source: wiktionary