Works that combine humans with non-human characters will often have the non-humans walking around stark naked (or as close as the Moral Guardians will allow) as they go about their everyday business. Genitals are never shown; at best, these beings might wear a Seashell Bra or Fur Bikini to avoid Squicking their human companions.
While they will seldom mention any discomfort, savvy viewers might wonder how they regulate their body temperature or protect against environmental dangers, especially if they lack fur, feathers, scales, or something comparable. If the topic is raised, it'll usually be justified as either a religious or cultural norm, or Bizarre Alien Biology.
One might also wonder about the lack of pockets, though this might also be an issue for normally dressed humans in some settings.
Functionally, this helps to emphasize the otherworldly nature of the characters, as it contrasts the awkwardness of undressed humans against the easy comfort of the naked aliens/fairies/demons/whatever. It's also an easy excuse to provide some Fanservice or comedy, though (sadly) almost always averted with Human Aliens.
Also see Barbie Doll Anatomy, Fur Is Clothing, Monster Modesty, Our Nudity Is Different, and Non-Humans Lack Attributes. Creatures with a Clothing Appendage may look clothed but actually be this. Compare National Geographic Nudity for a concept a little closer to home. Contrast with Little Green Man in a Can. The opposite trope of Enclosed Extraterrestrials. Not to be confused with a Broken Masquerade, which involves extraterrestrials (or otherworldly beings in general) being "exposed" to the skeptical masses.
- Dragon Ball Z. Freeza and his brother Cooler wear nothing at all in their final forms. Their father King Cold wears only a cape, chest armor and Underwear of Power. Played With, as supplementary materials reveal the white (or other colors) parts of their bodies are actually a 'bio suit' their species is capable of generating, essentially being clothing generated from their bodies. Which means that while Freeza's final form looks naked, he's actually wearing full body armor.
- Teen Titans: According to Starfire, Tamaranians don't place much value in clothes (they see nothing inherently unchaste about nudity and they're pretty much Flying Bricks, so Armor Is Useless). This is largely her justification for being both an Innocent Fanservice Girl and Ms. Fanservice.
- Martian Manhunter's true martian form has no clothes, and he merely shapeshifts forms that have clothes.
- Babe in the second Atari Force series goes around wearing nothing. Justified as he's from a species that grow into mountains, and his "skin" has the consistency of granite.
- In all of their incarnations, the Teenage Mutant Ninja Turtles are seldom seen wearing anything besides their bandanas and weapons, unless it's part of a disguise. Their shell is not of the removable kind.
- Martinex, of Marvel Comics's Guardians of the Galaxy, is a crystaline alien from the planet Pluto. His body is composed entirely of crystal, and never wears clothes.
- Plan 7 of 9 from Outer Space. Captain Proton tries to arrest an alien abductor for murder, kidnapping, reckless endangerment, and public indecency. "Why do non-humanoid aliens go around without clothes anyway?"
- Most My Little Pony: Friendship Is Magic Human-in-Equestria fanfics feature an inversion, even if it is never mentioned. The (alien) humans almost always wear clothes in a society that only ever wears clothing to formal events, and is otherwise naked 98% of the time.
- Actually justified in Peter Watts The Things, a take on The Thing (1982) as told from the alien's POV. To a creature that can shapeshift and adapt to any environment, the idea of clothing is weird and horribly inefficient.
"It feels almost obscenean offense against Creation itselfto stay stuck in this skin. It's so ill-suited to its environment that it needs to be wrapped in multiple layers of fabric just to stay warm. There are a myriad ways I could optimize it: shorter limbs, better insulation, a lower surface:volume ratio. All these shapes I still have within me, and I dare not use any of them even to keep out the cold. I dare not adapt; in this place, I can only hide."
- When Crystal and Amber are revealed to be aliens in Scooby-Doo and the Alien Invaders, their true forms appear to lack clothing.
- In Bill & Ted's Bogus Journey, the Station aliens are always naked, despite having furless skin and minimal body hair.
- E.T. the Extra-Terrestrial is another naked hairless alien. Lampshaded:
Gertie: Was he wearing any clothes?
- The alien family in Mac and Me, until they become American citizens at the end.
- Star Wars
- Chewbacca is probably the most well-known example, though he does solve the pocket problem by wearing a Badass Bandolier. He's also covered in enough fur that protection from the elements is a non-issue.
- Hutts are always shown undressed, despite a lack of natural protective covering. Hutt hides are thick enough to shrug off blaster fire, though.
- Mostly averted with Paul from the 2011 comedy. He needs to be naked to turn invisible effectively, but the rest of the time, he wears cargo pants apparently hiding a Gag Penis.
Paul: What? This is small where I come from!
- Almost every alien in Men in Black, save for the ones with a Mobile-Suit Human.
- The aliens in Signs wear nothing. This seems rather stupid when it's revealed at the end that water reacts to their skin like acid. So they're purposefully choosing to run around a planet covered in over 70% acid. That'd be like streaking on Venus.
- The alien in Super 8. If the alien had any garments, it's possible that they were confiscated for analysis by its human captors.
- The aliens from Cowboys & Aliens only ever wear their gun-bracelets. It helps that most of their skin is Immune to Bullets, though.
- The movie version of The Lion, the Witch, and the Wardrobe averts the matter of topless centauresses by putting them in (torso-only) armor.
- Averted in Independence Day: What initially looks like naked aliens is later established to be some type of environmental/combat suit. Under the suit they're naked.
- Pretty much all the aliens in Animorphs, except for some Yeerk hosts who wear minimal clothes to depict rank or faction. When Elfangor first met humans he was actually freaked out by Loren taking off her shoe, since he had assumed that was her actual foot. Ax has trouble understanding why he has to wear clothing while morphed as a human, and frequently refers to clothes as "artificial skin" and shoes as "artificial hooves."
- Lampshaded in one of the Sector General novels, when Dr. Conway muses that he should be able to easily find the Earth Humans among the crowd at the space station's "beach" by the fact that only they would be wearing clothing.
- The Martians of Edgar Rice Burroughs' John Carter of Mars novels are confirmed nudists, despite the harsh conditions on Barsoom. Dejah Thoris, in her first appearance, is described in these immortal words: "She was as destitute of clothes as the green Martians who accompanied her; indeed, save for her highly wrought ornaments she was entirely naked, nor could any apparel have enhanced the beauty of her perfect and symmetrical figure."
- In Turtledove's World War series of books, the Race never wears clothes. Their idea of proper attire is to cover themselves with body paint. Somewhat justified in that the planets they had visited before were very, very hot, like their home star. Example: their polar regions on Home (the Race's home world) are famous for going down to sixty degrees Fahrenheit. They are utterly unprepared for Earth's far chillier climate, and suffer greatly in their campaigns in the USSR and America during the winter months.
- In the follow-up Colonization series, the lack of clothing also causes problems with the Race's subjugation of Muslims, especially once the Colonization Fleet arrives, and females of the Race start to show up (although it's difficult for humans to distinguish Race males from females). One Muslim man asks a couple of Race soldiers (males) why they allow their females (and males too) to walk around naked. After all, aren't their minds constantly busy with thoughts of sex? The soldiers laugh at the notion (they only mate during the females' season and don't think about mating the rest of the year). The Muslim man proceeds to mention how Allah frowns upon such thoughts, and the soldiers casually mention not caring what some fictional deity thinks. The man looks at them in shock and leaves. Violent riots start soon after.
- By The '60s, many younger humans (in warmer regions, at least) have started to wear the bare minimum of clothing, prefering Race-style bodypaint. In fact, some wear nothing at all. By the 21st century, it's common to show nudity on TV, and the most popular show on American TV is a gameshow where the assistant is a hot girl named Rita who wears Minoan-style clothing (i.e. fully-exposed breasts), and many women in the audience are also topless (and not all are covered in bodypaint). At the same time, the host of the show is a human-raised lizard named Donald who puts on bodypaint for the show that makes it look like he's wearing a formal suit.
- Centaurs in Piers Anthony's Xanth series take pride in being nude, they see it as confirming their superiority to the rest of the world. One side character in one of the books has to take on this attitude after having gone through a transformation in order to be with her Centaur boyfriend, with limited success.
- Larry Niven's Known Space: Protectors are transformed humans who've lost their gonads and gained enhanced intelligence. They put as much thought into protecting their groins as you do into protecting your armpits, and largely for the same reasons in addition to their skin already having hardened into a kind of biological armor. However, many of them see the value of carrying things, so they wear multi-pocketed vests.
- E. E. Doc Smith featured this in both the Lensman and Skylark universes, both with human (or humanoid) extraterrestrials and with definite non-humans (including flying lizards and even more grotesque forms). Whole planets were basically giant nudist colonies in space, with the inhabitants giving no more thought to their unclothed status than to the food they ate. Some races invert the trope.
- In the Discworld, the troll Detritus is described, in Moving Pictures, as naked except for a ragged loincloth that concealed whatever it was that trolls thought necessary to conceal. This appears normal for trolls.
- In C. S. Lewis's The Space Trilogy, the inhabitants of Malacandra (Mars) and Perelandra (Venus) wear clothing for function or beauty, not modesty. The furry Hrossa wear belts with pouches and the froglike Pfifltriggi wear pocket-covered vests. When Ransom visits Perelandra, it doesn't take long before he ditches his clothes because that's just what people do on Perelandra.
- The nonhumanoid aliens in Alien In A Small Town have no nudity taboo, but do wear functional clothing. The title alien wears a "life support belt" attached to surgical implants which helps him breathe Earth's atmosphere, and a translator device on a strap around his eyestalk.
- Lilith's Brood: The Cthulhumanoid Oankali only wear clothes when they're deliberately trying to put humans at ease. Justified since they have sensory tentacles across their bodies, are tough enough not to need the protection, don't have (or need) genitalia, and come from a Planet Spaceship that maintains a safe environment for them.
- In Rick Griffin's Hayven Celestia universe most sapient species are covered in fur or scales and wear little more than jewelry and tool belts. Unless they're in hazardous environments like open space or the krakun's sulfur-saturated homeworld.
- Played for laughs in Hunting Problem, a 1950's sci-fi by Robert Sheckley. A shapeshifting Starfish Alien is hunting three humans so he can bring back a Genuine Human Hide. He finally succeeds in capturing them, pulls out a knife and...we cut to the three humans racing away in their spaceship, wondering why some alien would steal their clothes.
- ALF is smart enough to crack wise with the Tanners, but can't be bothered to put on a pair of pants.
- Averted in later episodes when he starts wearing clothes.
- Stargate SG-1: The Asgard are highly advanced grey space aliens, but never wear clothes. They quite visibly have no genitalia, since they reproduce through cloning. Lampshaded when both Sheppard and Mitchell first meet them, and their primary concern is wondering if Asgard are supposed to be naked.
- "Grey" aliens in The X-Files have no clothes. Except for the episode "Unnatural", when the Grey is wearing baseball clothing.
- Odo from Star Trek: Deep Space Nine is ''technically'' naked most of the time, but since he's a shapeshifter it looks like he's wearing clothing and it's never really commented on. Of course, Odo's natural state is a gelatinous blob with no clearly defined organs, much less genitals.
- Doctor Who:
- The Sea Devils had to be given string vests at the last minute as someone objected to this issue late into production.
- The Slitheen when not in human suits. They even rejoice in their nakedness.
- While the Teller walks around in a full-body straightjacket for most of Time Heist, he and his mate are released wearing nothing at all.
- Cole in Tracker, who had a hard time with clothing, and staying dressed in the beginning, probably related to Cirronians being energy beings.
- The 2016 Arrowverse crossover event, "Invasion," features the Dominators, who are completely naked, in contrast to their comic counterparts. The producers said they were originally going to wear robes, but found them difficult to animate when they decided to make the aliens entirely CGI.
- Journey into Space: In Journey to the Moon / Operation Luna, the Time Travellers do not wear clothes due to their armoured shells.
- In the indie game Fez, Gomez and all the other characters do not wear any clothing.
- The character Cosmo from the old MS-DOS game Cosmo's Cosmic Adventure.
- The titular character from the Kirby series only wears red shoes and sometimes hats. Justified since he is only a ball with limbs.
- In Spore, you can create an outfit for your creature in the Tribal, City, and Space stages. You do have the option of not giving them clothing but they will be weaker in Tribal stage. In the City and Space stages, clothing is only aesthetic.
- ZigZagged across the franchise with the Brutes. In Halo 2, their standard uniform, from their infantry to their Chieftain, is a bandoleer, a neck guard and maybe a metal helmet and some shoulder pads, and that's it (though to be fair, it's not like they really need much else: most of their important bits are covered by their fur and their naturally thick hides make them as tough as any fully armoured Spartan or Elite), while the Brutes in Halo 3 are all decked out elaborate suits of Powered Armor. The Halo EU explains that there are two main "meta-clans" of Brutes, with one being more savage and primitive and the other more intelligent and sophisticated, explaining the contrast between the two games. The Brutes in Halo: Reach split the difference; low-ranking grunts go nude while high-ranking commanders wear armor. The real life explanation for this is that Halo 2 had a very rocky development, with a large amount of content tweaked or completely removed to meet publisher deadlines.
- Until Halo 5: Guardians, the standard Grunt wore a helmet, some chest armor, a methane backpack, and absolutely nothing else. In this case, the Grunts are cannon fodder who are not given much in the way of good equipment by their superiors.
- Only six of the nine standard races seen in Startopia bother with clothing.
- In X Rebirth, the Lizard Folk Teladi rarely wear anything more concealing than a utility vest and a backpack, showing that they got nothing down there. Averted by their appearances in the older games, where they were often shown wearing armor, shirts, and vests, though they were only ever shown from the shoulders up, and were more anthropomorphic then.
- Varies by alien in the XCOM: Enemy Unknown but the Sectoids, Outsiders, Faceless and Codex are the most notable nudists. Justified in the case of chryssalids because they're just living weapons. The trope is averted by all other species.
- Zig-zigzagged in XCOM 2: The berserker in 2 seem to be naked in comparison to the berserkers in 1, and the Andromedon is nude under its pressure suit.
- While most species in Stellaris wear Space Clothes, some don't, particularly in the Arthropoid group. The game actually keeps track of this, allowing custom insults from nudists to clothes-wearing enemies:
Behold the [Species 1] form, glorious and bared for all to admire. Contrast with the paltry [Species 2], cowering under their layers of cloth, knowing that the world does not want to see their sad frames.
- Vasudan fighter pilots in Freespace are shown to wear armour-esque flight-suits just like their Terran counterparts, but otherwise every Vasudan shown wears not a speck of clothing. And show nothing.
- Averted by most species in Mass Effect, but notably played straight by the hanar. Of course, given that the hanar are a species of floating jellyfish, it's difficult to think of what clothing they could possibly wear in the first place. Especially since they communicate by bioluminescent flashes.
- Starcraft has the Protoss, who play with this trope a bit. Although they largely appear to be Human Aliens, they are in fact sentient plants/fungi. Thus, they not only lack anything resembling mammalian genitalia (including being a rare subversion of Non-Mammal Mammaries), they also do not feel sexual desire (at least, not in the way humans do). They tend to wear little in the way of clothing, and even their armor has a tendency towards the stripperific. However, the few articles of clothing they do consistently wear are those which would cover genitalia on a human. On the other hand,their apparel choices need no justification.
- also in that game, a rare example of this with Human Aliens is Sarah Kerrigan in her Queen of Blades form (and in her final Xel'naga form). Technically, she spends much of Starcraft 2 naked: though nothing resembling human genitalia shows (since her body was reassembled and "improved" by Abathur). Though whatever the crazy space slug did, it doesn't seem to put Jim Raynor off (or indeed most of the fans).
- Used hilariously in Irregular Webcomic! involving Han Solo and Chewbacca.
- See the centaurs bit above? In Accidental Centaurs, when encountering civilization for the first time, Alex learns at his expense that not covering one's upper half is considered indecent exposure for males too.
- The Uryuoms from El Goonish Shive, being shapeshifters, can simply "delete" their private parts when not in use. However, none are seen naked outside of Imagine Spots, when it's also specified they do have use for clothing.
- Jix and other Ambis usually don't wear anything except for occasional battle armor. Leading to several "did you just pull that out of your ass?" comments whenever one draws a gun (canonically they keep things in subspace, just like their extra mass for battle form).
- All the non-human characters in Marooned.
- Zigzagged for Gwog and his species in The Petri Dish. They don't have a nudity taboo but usually wear clothes anyway. Gwog's pet wears only a collar.
- FTL: Kestrel Adventures:As in the game many aliens seem fine with walking around naked. Lampshaded in one episode when one of the humans notices a clothed rock man.
- According to Cracked, this is one of the reasons Aliens have a hard time conquering Earth.
- Most nonhuman species in The Jenkinsverse hail from comfortable, hospitable planets. While clothing is useful for protection and warmth on Death World Earth, elsewhere in the galaxy clothing would have just been unnecessary effort in creating and cleaning it for no real benefit. Most alien species are therefore rarely clothed, except for some packs, bags and holsters in lieu of pockets.
- Roger from American Dad! was like this in the earlier seasons, before he realized he could go out in public and pass for human with clothes and a wig. His home planet is actually much colder than Earth, so he has no problem with exposure to the elements.
- Gwen's grandmother in Ben 10: Alien Force. Of course, her entire body is luminescent. This actually seems to be the true form of all Anodites.
- Most of Ben's alien forms fall under this. Lampshaded in Omniverse where he meets a fully clothed specimen of one of them (with a culturally developed sense of shame) and realizes that form has been completely naked the whole time.
- Frisky Dingo: Killface, the Villain Protagonist, doesn't wear any clothes and few people seem to mind. His son Simon does wear clothes, making it all the more bizarre. Played with at the last moment of the series, when Killface's family, dressed royally, comes to Earth on their spaceship. His mother gets mad at his lack of clothes.
- Rivesh Mantilax and Seruba Velak, from the Doctor Who animated serial Dreamland.
- The Transformers, as a race of living Transforming Mecha, rarely wear clothes... though occasionally they choose to put some on, for whatever reason.
- Worth noting is that when Transformers do wear clothes, they usually need to ditch them to transform anyways, so it may be one of the rare cases where clothing actually is less practical than nudity.
- This trope appears amongst several of the various aliens that appear in Wander over Yonder, including the main duo, Wander and Sylvia, who only wear accessories that don't really cover anything. Lord Hater, Commander Peepers, and the watchdogs are far more modest though.
- My Little Pony: Friendship Is Magic: The titular ponies only ever wear clothes for decorative purposes (other than guards wearing armor), and outside of special occasions tend to limit themselves to a hat, tie or other accessories. Despite this, Equestria has a thriving fashion industry, and one of the protagonists is (by season 6) running three separate boutiques across the country.
- Tripping the Rift: Chode is always naked. Interestingly other members of his species like his grandfather do use clothes, so go figure.