Calvin and Hobbes by Bill Watterson for May 13, 1987
Calvin: You made a mistake, didn't you? Hobbes: No, I can cover it up. Calvin: Cover what up? What did you do wrong? Hobbes: Nothing. I can't help it if your head has a funny bump that make the scissors go screwy. Calvin: Your head's gonna have "funny bumps" in a minute if you don't tell me what you did!! Hobbes: Oops. Hold still. Calvin: Why'd you say "oops"?! What'd you do now?! Hobbes: Nothing. Let's try parting your hair from ear to ear.