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Its first appearance is in "Squid's Day Off," in which Squidward mistakes its shadow behind the shower curtain for SpongeBob while having constant hallucinations of the latter constantly asking him "Are you finished with those errands?," due to having to visit the Krusty Krab every moment in order to check up on SpongeBob so he doesn't do anything drastic during Squidward's vacation.
In the episode "House Fancy," Patrick comes running into Squidward's house, telling him that he desperately has to use the bathroom. After Patrick finishes, the toilet comes crawling out of the bathroom in agony. Its only lines were, "Please, somebody put me out of my misery!" and "Have mercy on my soul!" before dying in Squidward's arms. It comes back to make a brief appearance in "Choir Boys," where it is shown with Squidward's Toilet Paper, whose only line was, "Don't feel bad. He did not use me yesterday either."