The toilet 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.
Role in series
"Squid's Day Off"
Squidward mistakes his toilet's 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 to check up on SpongeBob so he doesn't do anything drastic during Squidward's vacation.
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.
While visiting SpongeBob’s house to retrieve his vacuum, Squidward finds it is renovated to look just like his house. In the bathroom, Squidward is startled to the point where he falls and bangs his head on the toilet, knocking him out.
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.