No, trypophobia of the skin is not a real disease. It is actually a fear of clusters of roughly circular shapes that may cause goosebumps on the skin, which, again, are clusters of circular shapes. Goosebumps, or piloerection, are tiny elevations of the skin and standing up of hairs, usually on the arms and legs. Caused by the contraction of tiny muscles at the base of hair follicles, they are mostly temporary.