Humor is one of the endearing qualities of To Kill a Mockingbird, and there are countless examples throughout the novel. Scout's narrative is filled with humorous bits of reflection and observation, and it often comes to lighten serious moments. At the jail on the night the lynch mob appears, the men begin to manhandle the children, and they appear to be ready to go after Atticus next before taking care of their murderous business with Tom. But Scout intercedes.
"Don't you touch him!" I kicked the man swiftly. Barefooted, I was surprised to see him fall back in real pain. I intended to kick his shin, but aimed too high.
Scout's kick to the groin was not the only example of off-color humor to tickle the reader's funnybone. Her tale of Mr. Avery's long-lasting and long-distance act of self-relief amazed the children before they undertook their raid on Boo's back porch (in Chapter 6).
... Dill stopped us. "Golly, looka yonder"... a closer inspection revealed an arc of water descending from the leaves and splashing in a yellow circle of the street light, some ten feet from source to earth... Dill said he must drink a gallon a day, and the ensuing contest to determine relative distances and respective prowess only made me feel left out again, as I was untalented in this area.
Dill offers comic relief in several chapters, though he is really a tragic character, deserted by his parents each summer in Maycomb. But Dill is at his happiest when he stays with his Aunt Rachel, and they are Scout's best days, too. Dolphus Raymond also offers a humorous respite from the serious nature of the trial when he reveals to Dill and Scout the true ingredient that fills the bottle hidden in his paper bag: It is not whiskey, but Coca-Cola.
I had a feeling that I shouldn't be here listening to this sinful man who had mixed children and didn't care who knew it, but he was fascinating.
Miss Stephanie offers a bit of comic relief with her ridiculous gossip, occasionally serving as the butt of Miss Maudie's own jokes. But her attempt at off-color humor after Nathan Radley has fired his shotgun at prowlers (actually Jem, Scout and Dill) merely shows her own racist attitude.
"... (Mr. Radley) Shot in the air. Scared him pale, though. Says if anyone sees a white nigger around, that's the one."
And Miss Maudie's large derriere provided a "generous target" for both Scout's unloaded air rifle and for a rare glimpse of Atticus's sense of humor.
He pushed his hat to the back of his head and crossed the street. "Maudie," he called, "I thought I'd better warn you. You're in considerable peril."
Miss Maudie straightened up and looked toward me. "Atticus, you are a devil from hell."