The Iconography of the skanker, was first an album cover for the hardcore punk band the circle jerks, another form of icon was often used by the band dri in a stick figure form. A skanker is someone who typically "skank's" a dance performed to many different types of music.
It's extremely similar to the Hardcore dance "two-step"
See the pit at a ska show for the most common example of a skanker.
"Damn that skanker is skanking fast"