crotch floss

(n.) a towel (or other piece of material such as an article of clothing left in the bathroom by a roomie or sibling) purpose-dedicated to drying the area between one's genitals and rectum and the rectum itself (also the region between the scrotum and the thigh). The towel is grasped in one hand in front of the body, and one hand behind and pulled back and forth vigorously, as if flossing one's teeth, but on a larger and smellier scale. (v.) to floss one's crotch, using a towel as described above. Telltale evidence is usually left on a towel used for crotch flossing: brown skid marks.