It's overlining (drawing lip liner over/beyond the natural lip line) to create an exaggerated shape/make its lips look larger. This "tall upper lip not as wide as the lower lip" look is a new and horrible trend I'm seeing in a few places. The idea, I think, is to create a cute sort of Betty-Boop-esque or pooched-up lip, sort of like you're making a kissy face but without actually making the face...but it rarely works, and especially doesn't work on pigs.