Because this is a picture of Onion's reaction to panting, which is to bite whatever is near his mouth, I thought it was sideways related to the topic at hand.
Palinode: Whatcha doing?
Schmutzie: I'm taking off my pants...
Palinode: Really? [His face breaks out in a huge grin.]
Schmutzie: ...and I'm putting on some other pants.
Palinode: Oh. [His grin falls.]
Schmutzie: What?
Palinode: Well, it's just that your sentence started out really interesting, and then it ended up being really boring.
Next time I put on pants, I'll try to throw in a little soft shoe or something.