Demon Giles: Yes, just a little, uh... Hurts when I sit.
Spike: I mean someone's following us!
People Sit on Chairs — except when those chairs are built for someone else's anatomy.
This is when one species has trouble with furniture made for another species or size due to differences in anatomy, size, or culture. A common example would be a Winged Humanoid or Lizard Folk (with their thick and/or inflexible tails) having trouble sitting properly in chairs built for human use — or, for that matter, vice versa!
- A Centaur's Life: The many fantasy races of the series, most of which consider themselves human, have many different ergonomic needs met by thorough World Building. Centaurs wear specialized shoes and rest their abdomens on benches. People whose ears are at the tops of their heads wear glasses like these◊. Clothes with adjustable tail holes are standard, though angels are tailless. All public and recently constructed buildings are supposed to accommodate the size and weight of centaurs, though older apartment structures are exempt. In Japan at least it's considered discrimination for public stores to not account for and accommodate different species.
- There are a number of chapters in Daily Life with Monster Girl that revolve around the eponymous monster girls dealing with the fact that the world hasn't quite adjusted to fit their physiques yet. The centaur and spider girl probably get this the most, as they're both far too large to use normal human furniture, while the other girls can usually adjust better.
- In My Hero Academia, Mashirao Ojiro's quirk Tail means he has a lot of difficulty with chairs and such, since the people who designed most chairs didn't plan on people with tails sitting in them. He tends to like chairs with spaces in the back (like metal folding chairs), since he can stick his tail through the hole.
- The Far Side: In one strip, two stegosaurs are leaving another dinosaur couple, the (giant but recognizeably designed-for-humans) chair cushions still embedded on their back plates and spikes, with the wife telling her husband that's the last time said couple visits.
- Though he never complains about it, Frieza in Savior of Demons will usually turn chairs sideways before sitting to accommodate his Prehensile Tail.
- Turnabout Storm: Phoenix barely gets any sleep during his first night in Equestria thanks to how small pony beds are.
- D Taina did a fan comic illustrating the problems Gargoyles might have with chairs.
- Averted in Monsters, Inc.: Sulley's chair has a hole in the back of it to fit his tail.
- There's an examples of humans running into this in Forbidden Planet, where Morbius and the captain have difficulty with devices designed for the Krell, the aliens who once lived on the planet. Notably, it looks like their cranium were much wider.
- In Return of the Jedi, Chewbacca growls at the seats in the Imperial shuttle, and Han responds, "I don't think the Empire had wookies in mind when they designed her, Chewie."
- The seat in the space ship in Flight of the Navigator originally didn't fit the young male protagonist, and the ship had to make adjustments.
- In Star Trek VI: The Undiscovered Country, an Enterprise crewmember is suspected of murdering Klingon Chancellor Gorkon because of gravity boots found in his locker... and then immediately cleared, because the boots are designed for human feet and his feet are short, webbed, and nearly circular in shape.
- In both Attack of the Clones and Revenge of the Sith, Yoda is depicted as having a visibly smaller lightsaber handle than Jedi who are of more human proportions.
- In The Dark Crystal, the wisest Mystic is seen resting on a "bed" configured for his low-slung, long-tailed form, complete with a small wooden platform for his head.
- X-Wing Series:
- In Rogue Squadron, the first book of the series, Wedge becomes apprehensive when he learns that his Verpine crew chief has "tinkered" with his brand new starfighter, as he remembers horror stories from other human pilots of ships optimized for Verpine ergonomics. His X-Wing turns out to be fine, however.
- The novel series as a whole tends to Hand Wave how Twi'lek and other nonhuman pilots can fit their appendages inside flight helmets. It's averted in the comics, however, where nonhumans are depicted as having helmets with the proper ergonomics for their species.
- The Lizards in World War have trouble sitting on human chairs that don't accommodate their tails.
- Invoked in the last book of the Mage Storms trilogy: two characters realize an ancient desk was used by a hertasi (a lizard-like creature) because the stool next to it was backless and had a cutout to accommodate a tail.
- In the Garrett, P.I. series, Garrett has a special chair made for his ratgirl apprentice, Pular Singe, who has a long tail.
- In Chorus Skating, the turtle wizard Clothahump uses a chair with a deeply-concave back, built to fit neatly around his shell.
- At one point in the Animorphs series, the heroes steal a Yeerk fighter with the intent of blowing the invasion's cover by landing it in Washington, D.C. The Token Nonhuman Ax mans the gunner's "chair", which is actually more of a long stool since it's built for the centipede-like Taxxons. It fits Ax better than normal chairs since his species, the Andalites, are basically centaurs. Andalite ships are very uncomfortable for human passengers due to their lack of seating at all.
- Dinotopia has pictures of furniture built for dinosaurs. Apart from sometimes being much bigger than human furniture, it tends to take the form of cushioned benches to support the dinosaur's midsection rather than chairs.
- In the Heechee Saga; the chairs on the Heechee ships abandoned at Gateway asteroid all have V-shaped seats which are incredibly uncomfortable. Until humanity finally manages to meet the Heechee (halfway through the series), speculation runs rampant as to what Heechee hindquarters actually look like.
- The Humanx Commonwealth: The ant-like Insectoid Alien Thranx use form-fitted couches and saddle-like chairs that they can rest their thorax and abdomen on. In the First Contact prequels, they're completely flummoxed by human chairs.
- Sholan Alliance features an inversion. Sholans often use bowl shaped chairs which Carrie finds slightly difficult to use due to her smaller size. Also, later in the series, a visit to a popular restaurant involves a small stack of cushions.
- In Christopher Anvil's Pandora's Planet setting, there are two main intelligent species: Centrans, who have tails, and Earthmen. The human protagonist General Towers avoids Centran revolving chairs, because the user needs a tail to be able to adjust them safely.
- In Growing Wings, a preteen girl grows wings. They're huge and realistic enough that she needs specially-made clothes, stops being able to sleep on her back, and finds that sitting in a car seat for hours is agony. When she joins a tiny commune of other winged people she's introduced to their style of clothing and "wing socks" for very cold weather come up.
- Babylon 5 has an example where humans run into this trope, when Sheridan and Ivanova try to sleep on a tilted Minbari bed.
- Star Trek: Enterprise: The Enterprise crew has at one point to commandeer an Insectoid Xindi ship. Besides having trouble with the controls, which are rather alien, they also mention how much the seats are uncomfortable.
- In Shadow Operations, a Play-By-Email game based in the Star Trek universe, Ryramorl Ra'yral has difficulty sitting in most Starfleet chairs due to having a thick tail. Reepchip Charatetet must stand in most chairs as he is only 2'9" tall—completely average for his race.
- Inverted and played seriously in Earthdawn. The blood elves have thorns growing from all over their bodies; all the things they manufacture are enchanted to adapt, opening and closing holes as needed, but foreign furniture... suffers.
- Marc Miller's Traveller supplement Aliens Archive. The following alien species were specfically noted as having problems with human furniture due to their anatomies: Asym, Controlled, Denaar, Hana Saka, Newts and Tekundu (when engorged after drinking lots of water).
- The Unreal Engine had a major flaw where any character models had to have either a bipedal or quadruped form so that the engine could run the physics engine on moving character models and their skeletons without needing extensive modification of the engine. For this reason, the Elcor could never be enemies or multiplayer characters in the original trilogy.
- The Elder Scrolls V: Skyrim deals with this...by ignoring it. Tails of Argonians and Khajiit clip though any chair they sit on and though any armour they wear. Curiously they do have the correct pose/animation for sitting on the ground without clipping.
- The Sangheili/Elites of Halo were initially designed with a tail, but it was scrapped after one of the designers pointed out that due to this trope, the tail would be forced to go somewhere phallic.
- In the Mario & Luigi series, in the Yoshi theatre talking to one of the yoshis has him say that the chairs are comfy but his tail gets in the way.
- After Alexis has become a drider in Spinnerette, she complains about human-sized doors.
- El Goonish Shive:
- Grace has to use a car in her three-tailed form. She tries various ways of fitting into the seat until ending up "sitting" upside down, then she gives up and chooses to use the back seat.
- Another example shows Ellen learning something from her "Second Life":
Ellen: Alternate me worked in a clothing store. That's demanding enough without people with tails and extra arms.
- Dan and Mab's Furry Adventures has centaur-like Matilda living in a town populated mostly by bipeds. How she sits comfortably when she goes out isn't addressed, but we do see that she has a huge bed-sized couch.
- Averted in Winds of Terravum; public use furniture has a hole for Kamerum (cat-like Petting Zoo People) to thread their tails through.
- Kevin & Kell sometimes does the joke about how common items from every day life have to be designed for all the Loads and Loads of Animal Species.
- The chairs in the eponymous train of Dinosaur Train don't accommodate the dinosaur's tails, but the issue is never touched upon.
- In Futurama, a family of newly-arrived alien immigrants sets up a pizza parlor near Planet Express. The mother expresses concern about the U-shaped chairs they're using, since she heard that human knees bend down instead of up. The father assures her that if anyone complains, he can bend their legs the other way for free.
- On Dinosaucers, the control seats on the various spacecraft and bases were designed with a shoulder-height backrest supported on only one side, leaving room for the operator's tail to slide in.
- Most furniture in My Little Pony: Friendship Is Magic differs significantly from furniture designed for humans, allowing ponies to sit comfortably; this includes the use of cushions and straw piles as chairs and classroom desks with tilted seats. The one exception where this trope is Played Straight is when Lyra Heartstrings sits awkwardly on her haunches on a park bench◊, which instantly made her go memetic with a Fanon obsession with humans, while some fans pondered why such benches would even exist in Equestria.
- Joseph "The Elephant Man" Merrick had an armchair built for his unique body shape. He really, really needed a comfortable chair because his disability made it impossible for him to lie down, so he had to sleep in his chair.
- The house of Charles S. Stratton (aka General Tom Thumb) is notable for the absolutely tiny furniture within. Mr. Stratton stood less than 3 1/2 feet tall and his wife was even shorter.