What Lucy draws on the actual pumpkin. Violet's design has the mouth turn up but Lucy's turns down. Kind of a funny error I never really noticed before.
I always noticed that one and thought it was odd.
shareThis might be a reference to when Lucy is asked to smile, and instead, she frowns, no matter how hard she tries. It's a funny implication that Lucy is such a violent, angry, hateful bully-Karen that she can never be happy, she can never smile and she brings destructive energy wherever she goes.
This pumpkin thing would definitely match all these implications perfectly - not only can she not smile, but she can't even DRAW (or cut) a smile!
Obviously we see her smile many times in the strip and cartoons, but it's still pretty funny.