In the "There's Nobody Quite Like You" song number from "Ginger's Antenna Dilemma," after Basil joins the song and sings "So it isn't such a mystery she went down in history," Johnny raises his finger and opens his mouth as if he's about to sing the next line. He then looks somewhat bemused as Basil sings it instead, "She knew that who she was was a plus..."
In the same song, Ginger sings "Don't tell me I'm unique, that's absurd!" and Johnny replies in song "But you're one-of-a-kind, I give you my word!" Unique means one-of-a-kind.
Just about everything about the "Everything Must Go" song from "The Sprites Save Grotto's Grove," featuring special guest character Yolanda Ivanna Wanna (Ann Harada, one of Tartaglia's fellow Avenue Q alumni).
Throughout the song, the character totally invades Johnny's space, petting him, poking him, prodding him and otherwise causing him any number of Amusing Injuries, and at the end of the song leaving him cowering on his own doorstep. And the whole time she's singing about how she's going to blaze in and replace his entire backyard with a hotel/shopping mall complex.
Yolanda: You'll be keeping cool / In the indoor pool / Where your garden was!
Johnny: It was?!
From the same song:
Yolanda: Is this a tree?
Johnny: (with a "well, duh!" tone in his voice) Yes, it's a tree!
Yolanda: This we do not want.
Johnny: (incredulous) Do not want?
Yolanda: Chop it down tonight / 'Cause it's standing right / In my restaurant!
Sprites: What restaurant?!
In the same story, the Sprites use their magic to get rid of Yolanda. One of the tricks they use is for Ginger to summon up a localized raincloud that only rains on Yolanda.
Ginger: Clouds above, from everywhere, make it rain, but only there. Ha!
Yolanda: Stand back, Johnny-boy! (cloud rains on her) What is going on?!
Johnny: (cracking up) Uh, yeah, I should have warned you about the strange weather around here. Sudden sunshowers.