The limit of the Willing Suspension of Disbelief for a given element is directly proportional to its sexiness.
In other words, when things are sufficiently sexy, viewers will accept them, even when they are outright impossible, or just astronomically improbable in reality.
Of course, some of these cases can be justified In-Universe if the characters demonstrating this have radically different anatomy than ours or if they have a superpower that would justify this one way or another (such as shapeshifting or size alteration, for example).
A Super-Trope to:
- Breast Expansion: In reality, breasts can't suddenly expand.
- Censor Steam: In reality, steam is sometimes transparent, and can't be trusted in covering body parts when it isn't.
- Chainmail Bikini: In reality, you should not fight in bikini-shaped armor, because it protects only some vital areas but not others.
- Clothing Damage: In reality, clothing does not degrade in a conveniently alluring fashion.
- Combat Stilettos: In reality, you cannot run and fight in stiletto heels.
- Conveniently Common Kink: In reality, random happenstance is unreliable as a means for people with compatible obscure fetishes to find each other.
- Custom Uniform of Sexy: In reality, each uniform is standard. That's what the word uniform means.
- Deus Sex Machina: In reality, sex isn't something that you need to do to make something rather than human reproduction work.
- Exposed to the Elements: In reality, clothing inappropriate to the elements can prove harmful or fatal.
- Form-Fitting Wardrobe: In reality, a limit exists on how tight clothing can be (even when there is variance in material flexibility).
- Fur Bikini: In reality, you can't keep warm in a bikini made of fur, as it exposes too much of the body.
- Gendered Outfit: In reality, uniforms created for both genders consider practicality, rather than just showing as much skin as possible.
- Godiva Hair: In reality, hair cannot be trusted with covering body parts.
- Green-Skinned Space Babe: In reality, were aliens to exist, we (most likely) could not have sex with them.
- Hartman Hips: In reality, the human female body only forms a slight pear shape.
- Head-and-Hip Pose
- High-Heeled Feet
- High-Heel Power
- Hospital Hottie: In reality, hospital personnel dress for practicality.
- Hot Wind: In reality, wind does not appear just to make someone's hair and clothes move around seductively.
- Humanoid Female Animal: The character in question may be meant to be an animal In-Universe, but that won't stop the artist from anthropomorphizing them into what is essentially an attractive human woman from the neck down.
- Impossible Hourglass Figure: In reality, the human female figure forms only a slight hourglass, even in the most ideal figures.
- Impossibly-Low Neckline: In reality, any outfit that shows that much neckline would just fall off entirely.
- Intimate Healing: In real life, sex or sensual actions do not heal serious injuries.
- Latex Space Suit: In reality, space suits are bulky to protect the wearer. And the closest experimental suits require the wearer to pack putty or fluid-filled sacs around anything that would otherwise stick out (like breasts and groins).
- Most Common Superpower: In reality, were superheroines and villainesses to exist, they would not all have large breasts.
- Naughty Nuns: In reality, nuns are more chaste than most people.
- Naughty Nurse Outfit: In reality, nurses dress for practicality.
- Naughty Tentacles: In reality, were tentacles to become sentient, no reason would exist for sex with humans.
- Non-Mammal Mammaries: In reality, non-mammals don't have mammaries and even with mammals, they usually don't stick out like human breasts (not even primates).
- Orgasmic Combat: In reality, fighting does not sound like sex (and someone would have particular issues to get turned on by fighting).
- Panty Fighter: In reality, women using martial arts would likely NOT wear something that would almost always reveal her panties.
- Pink Is Erotic: The color pink represents eroticism and scenes of a sexual nature.
- Psychosexual Horror: A subgenre that explores psychosexual development as a subject matter, including themes of sexual development and sexual activities.
- Sex Magic: In reality, sex doesn't give you powers.
- Sexy Dimorphism: In reality, a non-human species most likely would not inexplicably have the female sex appear near-identical to attractive human women, despite the other sex being monstrous.
- She-Fu: In reality, such techniques are highly impractical in combat.
- Spy Catsuit: In reality, people cannot wear skintight clothing while remaining mobile and stealthy (barring flexible clothing material).
- Stripperiffic: In reality, people cannot wear revealing clothing unsuitable for the job.
- Suggestive Collision: In reality, when people collide, it's extremely unlikely that one person ends up pinned against the other person's sexy bits.
- Waif-Fu: In reality, women who are thatnote thin do not hit that hard. There are ways for small women to do damage in a fight, but it doesn’t look anything like it does on TV.
- World of Buxom: In reality, breasts come in various sizes, even small.
...but in fiction, we accept the alternative, because it's sexy.