Casual Nudity

Bob is estatic! He finally gets to interview his favorite author, Alice. He heads over to do the interview at Alice's private estate with her agent, only to discover that she is sunbathing "au naturel" at the side of her pool with some friends. Embarassed beyond belief, Bob turns around to give Alice a chance to save her modesty... but she doesn't, instead insisting on starting the interview immediately.

Unfortunately for Bob, Alice has no problems with Casual Nudity.

A character who partakes in Casual Nudity will often appear nude or partially undressed without any sexual intent, usually focused on a specific location -- home, the beach, the pool, et cetera. While Fan Service is not out of the question, the character itself generally will have no lewd intentions with their nudity -- they simply feel comfortable being nude in this particular situation and see no reason to dress.

On the most part they will understand the effects their nudity has on others, but this is generally not taken into consideration -- generally speaking, a person who is going casually nude will feel they have the right to do so at this particular place and time, despite any possible objections from others. This does not necessarily mean that they are comfortable being nude around anyone; indeed, the arrival of someone completely unexpected can very quickly change the situation, making it no longer ok to be nude at this particular time and place.

This can be indicative of a more comprehensive philosophy (Nudism / Naturism), a specific cultural thing, or merely a quirk of the character. This is occasionally used as a Establishing Character Moment -- Depending on how the situation plays out, the character can be played up as Mr or Ms Fan Service or The Vamp, a quirky Granola Girl, an extremely self confident (and / or manipulative) adult, or a ditz of the highest order.

A character's reaction to a situation like this can also be used as a Establishing Character Moment -- is the viewer confident enough to meet the naked character's gaze full on? Is he or she lascivious enough to sneak a peek (or openly leer)? Are they so timid they cannot even hold a conversation, instead stammering and trying desperately to get away?

The reaction of the other characters typically fall under two variants -- either the characters will be enchanted by the other character's nudity or they will be extremely uncomfortable being around a naked person -- characters that have other reactions (like calling their "buff" or joining in) are rare exceptions.

And, of course, the two characters' relationship can be hinted at through the use of Casual Nudity. A character who has no qualms about being seen nude around a specific other character be expressing that they feel the other character is beneath their notice, showing a lack of any romantic interest (but a deep friendship), or be trying desperately to break through the Just Friends barrier.

A common subtrope is to have the nude character honestly have No Nudity Taboo -- the character is completely oblivious that someone would find their nudity shocking and upsetting. An important difference between the two is that someone with No Nudity Taboo doesn't understand that others may have issue with nudity, someone enjoying Casual Nudity generally does, but doesn't care -- or at the least, assumes their current situation gives them the right to choose to be nude if they want.

The Foreign Exchange Student will occasionally be caught walking around the house naked or sunbathing topless, mostly because Europeans Are Kinky like that. In the US media, Casual Nudity was almost exclusively the realm of Foreign Fanservice for a great many years, although recent trends in various B-Movie franchises (and a growing acceptance of Casual Nudity in the younger population) has begun to change this.

Very much Truth in Television -- most cultures have varying views on what exactly is appropriate dress and where, with America having one of the more restrictive viewpoints on nudity and topfreedom. Topfree or clothesfree sunbathing is not an uncommon sight in European beaches and many parks and the use of Casual Nudity in European film, television, and advertising is not uncommmon -- things that would be absolutely unheard of in the United States.

Many cultures even have Casual Social Nudity -- Finland's love of nude saunas is legendary, and bath-houses and clothing-free hot springs in Japan are still communal to this day.

Advertising

 * There was an advertisement in the US for hot dogs that featured a bunch of casual nudists (with all the important bits hidden via Scenery Censor.)

Anime & Manga

 * Haruhi Suzumiya, having "no interest in ordinary humans," is perfectly willing to start changing with boys in the room, and Kyon compares this to a typical girl not having a problem changing in the same room as potatoes. This becomes a plot point: when she refuses to undress in the same room as Kyon, it's a sign that she's developing feelings for him.
 * Amuro Ninagawa of Umisho, who has no shame around someone she likes. Swimming naked is a hobby, and she considers taking a shower to be using a garden hose in the backyard of the male lead.
 * Mamiko Kuri from Narutaru prefers to be naked while she's indoors, to the shock and amazement of her visitors. Outside she wears little more than a flimsy dress (or on rare occasions, her school uniform). She's actually "closer to nature" in a way, since ; furthermore, while the nudity may be innocent, Mamiko's personality most certainly isn't.
 * Miharu and basically every human resident of the alien world Seiren from Girls Bravo have absolutely no restraint regarding nudity due to their planet being almost entirely composed of (apparently heterosexual) women. This, of course, allows the show to completely indulge in every kind of Fan Service imaginable.
 * Lala from To Love Ru has no qualms about walking around naked. Her excuse is that as a princess, she's always had servants help her bathe, dress, etc. so she's used to being nude around other people. It's important to note that other people of her race (including her family members) do not seem to share this lack of a nudity taboo.
 * In the original Ghost in the Shell movie, there is much nudity amongst Major Kusanagi and the other female cyborgs in the series. It's meant to invoke a detached nonsexual mood, emphasizing the mechanical nature of their bodies. As such, she has VERY few qualms about being naked.
 * In Kamisama Kazoku, protagonist Samataro's goddess mom is the Innocent Fanservice Girl, shamelessly mixing it up with a deep affection for her son that adds to the Oedipus Rex plot of the series. She goes so far as to fall asleep in her son's bed nude and he wakes her up to chastise her, she is completely unashamed about it.
 * A male has this role in Axis Powers Hetalia. North Italy is fond of getting some or all of his clothes off when he wants to sleep, which gets him often in trouble with others.
 * Brita from Darker Than Black has a teleportation power that inevitably leaves her with nothing but her Godiva Hair to cover her body.
 * Yuusaku in Toradora! apparently has No Nudity Taboo since one episode featured him nonchalantly walking into a room, in full view of the three main girls, with nothing covering him except a handtowel. He seems to have no idea why everyone seems to react strangely to this.
 * Night Tenjo from Absolute Boyfriend is another rare male example, being basically an android sex doll he assumes his lover will want to see him naked and is programmed to enjoy being naked. Riiko has to explain to him that stripping off quite so often is considered at least a bit unusual.
 * Kazuki Kosuda from B Gata H Kei struts around naked in her home, to the chagrin of her brother Takashi.
 * Louise from Zero no Tsukaima has no problem changing in front of Saito at first, because she considers him to be merely a servant. A few episodes later she hides in a closet to change, showing that she thinks of him differently.
 * Yuuko of Tasogare Otome x Amnesia sees no reason for modesty in her ghost form, stripping out of one school uniform to put on another right in front of Teiichi.
 * Mokuren in Please Save My Earth has her shower interrupted by Shion, who needs to update her security card. She lets him into her quarters, and searches frantically around the room for her security card, in the nude. This is because Mokuren was raised as a nudist. When she discovers her mistake she's embarrassed; not because Shion saw her naked, but because she embarrassed him.
 * Gray Fullbuster from Fairy Tail is a rare male example. In his training as an ice mage, his teacher made him strip down and stand in the snow in order to fully understand the cold. It became ingrained to the point of subconscious, as he'll need someone else to point out when he's mysteriously misplaced all of his clothing. Leon, who studied under the same teacher, seems to have the same problem.
 * Military servicewoman Jodie Bakuryu-Karen from Kochikame has no issue shown in her debut appearance. She attempts to take off her shirt if front her father and other men preparing for a shower and steps out of the door naked requesting a towel. Hard for Volvo for not being good with women always getting a nosebleed.

Web Original

 * Creamsicle: Other Girl-sempai can be interpreted as into casual nudity, if you see the black stripe as being a censor bar.

Western Animation

 * Family Guy - where the Griffin family meet the local nudists, a family relaxed about doing everything naked. Their son becomes Meg's boyfriend for a while. Friction is caused for a while by conflicting values.