Slime-o is a young green slug. In the 2007 book Abby Cadabby's Rhyme Time, Slime-o attends a sleepover at Oscar's trash can with Slimey the Worm and several Twiddlebugs.

Oscar the Grouch agrees to read Slime-o a bedtime story: Trash Gordon: Space Glory.

Observing the proceedings, Grover coos, "An itsy-bitsy pajama party! Is that not adorable?"