In my opinion, artist/creator Mark Tatulli does some of his best work on Lio when he plays with the conventions of the comic strip. Take this sequence from November 14, 2015. (click on image to enlarge)
The convention is that any marks that appear above a character don't really exist in the same space. They're text that only the reader sees to show the character's inner emotion.
Except in this strip.
The wrong punctuation is floating above Lio's head. He has to gather up the errant marks and hammer them into a new shape, like beating iron bars into horseshoes (not the sound effect).
Tatulli takes something that's understood to be immaterial and making it quite tangible. And once again draws the reader's attention to a blindly accepted convention. Brilliant.