Someone who consistently makes comments that cross the line. Someone who doesn't understand witty banter, instead moving to insults. Typically a meathead, or someone who lacks the intelligence to burn someone in a humorous manor...
Person 1: Dude, that shirt is a little chochy...

P.L.C.: Shut up, my shit looks tight, why don't you go fuck yourself...and your mother..

Person 1: Real funny bro

P.L.C.: Like your fucking face bro...hahaha...

Person 1: Dude, you are such a Perpetual Line Crosser.
by thechicynic February 15, 2008
Get the Perpetual Line Crosser mug.