Generally unclean or grubby person. One who avoids washing regularly. A person of questionable personal hygeine.
Festival Cop 1: See me when I twatted that soap dodger over the head?
Festival Cop 2: Yeah! I knobbled six of the scruffy fuckers today. Filthy fuckers...
Soap Dodger: That's harassment, maan. Babykiller!
Festival Cop 1: Right, you're fucking kneecapped.