Squidward's toilet is a toilet that first appears in the episode "Squid's Day Off" as a regular toilet, and in "House Fancy" as a character.
The toilet belongs to Squidward Tentacles and has had many different appearances throughout the series. Its seat is typically shown to be composed of bamboo, but in a few other episodes it is shown to look like a regular toilet seat.
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It makes its first appearance 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 makes another prominent appearance in the episode "Slide Whistle Stooges" when Squidward is briefly seen cleaning the toilet.
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."
In "Squid's Day Off," "Squid Wood," and "Pineapple Fever," Squidward has a bamboo toilet set, but in "House Fancy" and "Choir Boys," he has a regular toilet seat. It is possible he got a new one sometime after "Squid's Day Off."
Characters have popped out of Squidward's toilet twice.
In "The Two Faces of Squidward," Evelyn is seen popping out of Squidward's toilet.
In the short "Surfing Dreams," SpongeBob is seen popping out of Squidward's toilet.