A combination of "lurk" and "sneak." Means you're doing something clever and naughty. Can also represent someone shady or creepin.
Look at that slerkin guy over there!
I was slerkin around in the bushes outside your window.
She is such a slerk.
when you get mind blowingly drunk for a period of three or more days.
Dude, i went on this 6 day bender after we lost the race.