No offense but Jerec needed some chap stick. Go ahead, load up JK he is licking his lips in every scene.
Now every Dark Jedi knows that licking dry lips makes the problem worse. You need something to lock in the moisture into the skin and promote natural protection on the lips.
Maybe he liked to toture himself everytime he ate salty or spicy foods those flavors would find there way inside the hundreds of microscopic cracks in his lips and cause intense, crippling burning.
Perhaps frequent use of the lightsaber causes lips to dry and crack?
"Dark Jedi don't waste their force revive on fallen n00b Jedi." -anonomus