The history of cinema is boys photographing girls.The limit of the Willing Suspension of Disbelief for a given element is directly proportional to its degree of sexiness. In other words, when things are sufficiently sexy, viewers will accept them, even when they are outright impossible, or just astronomically improbable. A Sister Trope to Sex Sells. Compare Rule of Funny, Rule of Cool.
A Super Trope to:
- Breast Expansion: In reality, breasts can't suddenly expand.
- Chain Mail 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.
- Custom Uniform of Sexy: In reality, each uniform is standard.
- Deus Sex Machina: In reality, sex is not magical.
- 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).
- Gainaxing: In reality, breasts do not bounce that much, especially if they're larger and heavier!
- Gendered Outfit: In reality, uniforms created for both genders consider practicality, rather than just showing as much skin as possible.
- 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 body only forms a slight pear shape.
- 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.
- Impossible Hourglass Figure: In reality, the human figure forms only a slight hourglass even in the most ideal figures.
- 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.
- 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 in it).
- 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 carry out jobs while wearing clothing unsuitable for the application.
- 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, svelte women do not hit that hard.
- World of Buxom: In reality, breasts come in various sizes, even small.
...but in fiction, we accept the alternative, because it's sexy.